BPSC

Mental Ability & Reasoning

Q1021–Q1070 · 50 Questions
Reasoning — Number Series
Q1021EasyBPSC Prelims
Find the next number: 5, 10, 20, 40, 80, ?
A100
B120
C160
D200
Show Answer
✔ C — 160
Pattern: Each term is multiplied by 2
5 × 2 = 10
10 × 2 = 20
20 × 2 = 40
40 × 2 = 80
80 × 2 = 160
This is a geometric progression with ratio 2.
*Why A is wrong:* 100 = 80 + 20; adding 20 follows no consistent pattern here.
*Why B is wrong:* 120 = 80 × 1.5; the ratio would need to be 1.5, but all previous ratios are 2.
*Why D is wrong:* 200 = 80 × 2.5 or 80 + 120; neither is consistent with the established ratio of 2.
Reasoning — Analogy
Q1022EasyBPSC Prelims
Doctor : Hospital :: Teacher : ?
ASchool
BBook
CStudent
DClassroom
Show Answer
✔ A — School
Relationship: A professional works at their designated workplace.
Doctor works at a Hospital.
Teacher works at a School.
The analogy is: Professional → Workplace of that professional.
*Why B is wrong:* Book is a tool/resource used by a teacher, not their workplace.
*Why C is wrong:* Student is the recipient of the teacher's work, not the workplace.
*Why D is wrong:* Classroom is part of a school, but the broader workplace is the School — just as Hospital (not operating theatre) is the doctor's workplace.
Reasoning — Classification (Odd One Out)
Q1023EasyBPSC Prelims
Which is the odd one out?
ABihar
BJharkhand
CPatna
DUttar Pradesh
Show Answer
✔ C — Patna
Bihar, Jharkhand, and Uttar Pradesh are states of India.
Patna is a city (the capital of Bihar), not a state.
All others belong to the category of "States of India." Patna is the odd one out as it is a city/district.
*Why A is wrong:* Bihar is a state — belongs with the group.
*Why B is wrong:* Jharkhand (bifurcated from Bihar in 2000) is a state.
*Why D is wrong:* Uttar Pradesh is a state bordering Bihar.
Reasoning — Coding-Decoding
Q1024EasyBPSC Prelims
If CAT = 3120, what is DOG = ?
A4157
B4167
C4158
D5167
Show Answer
✔ A — 4157
Each letter is replaced by its alphabet position, written side by side: CAT = 3, 1, 20 → 3120.
DOG = D(4), O(15), G(7) → 4157.
❌ B (4167), C (4158): wrong digit for G. ❌ D (5167): wrong digit for D.
Q1032MediumBPSC Prelims
In a certain code, PATNA is written as RCVPC. How is BIHAR written in that code?
ADKJCT
BDKICT
CDJJCT
DDKJCS
Show Answer
✔ A — DKJCT
Each letter shifts forward by 2 positions in the alphabet:
P → R (+2), A → C (+2), T → V (+2), N → P (+2), A → C (+2)
PATNA → RCVPC ✓
Apply the same rule to BIHAR:
B → D (+2)
I → K (+2)
H → J (+2)
A → C (+2)
R → T (+2)
BIHAR → DKJCT
*Why B is wrong:* DKICT has I in position 3; H+2=J, not I.
*Why C is wrong:* DJJCT has J in position 2; I+2=K, not J.
*Why D is wrong:* DKJCS has S in position 5; R+2=T, not S.
Reasoning — Direction Sense
Q1025EasyBPSC Prelims
Ramesh starts from his house, walks 4 km North, then 3 km East. How far is he from his starting point?
A5 km
B6 km
C7 km
D7 km (in North-East direction)
Show Answer
✔ A — 5 km
Ramesh walks 4 km North and 3 km East.
By Pythagoras Theorem:
Distance = √(4² + 3²) = √(16 + 9) = √25 = 5 km
This is the classic 3-4-5 right triangle.
*Why B is wrong:* 6 = 4 + 3 (straight addition), which ignores the angle between directions.
*Why C is wrong:* 7 is not derived from any valid calculation of this path.
*Why D is wrong:* While North-East is the direction, the distance 7 km is wrong; correct distance is 5 km.
Q1033MediumBPSC Prelims
A man starts from Point A, walks 10 km South, turns left and walks 6 km, turns left again and walks 10 km. In which direction is he now from Point A, and how far?
A6 km West
B6 km East
C6 km North
DAt Point A
Show Answer
✔ B — 6 km East
Starting at A:
1. Walk 10 km South → reaches Point B (10 km South of A)
2. Turn Left (now facing East) → walk 6 km East → reaches Point C
3. Turn Left (now facing North) → walk 10 km North → reaches Point D
Point D is 10 km North of Point C, and Point C is 6 km East of Point B, and Point B is 10 km South of A.
So Point D is at same latitude as A but 6 km to the East.
He is 6 km East of Point A.
*Why A is wrong:* West is the wrong direction; turning left from South gives East, not West.
*Why C is wrong:* North would be if he overshot A, but he walked exactly 10 km North after going 10 km South — returns to same latitude.
*Why D is wrong:* He would be at A only if he had walked West 6 km in step 2 (not East).
Reasoning — Blood Relations
Q1026EasyBPSC Prelims
A is the father of B. C is the sister of B. D is the mother of A. What is D's relation to C?
AMother
BGrandmother
CAunt
DSister
Show Answer
✔ B — Grandmother
A is the father of B and C (C is B's sister, so A is also C's father).
D is the mother of A.
Therefore, D is the mother of A, who is the father of C.
D is C's Grandmother (paternal grandmother).
*Why A is wrong:* D is A's mother, not C's mother; D is C's grandmother.
*Why C is wrong:* Aunt would be A's sister's relation to C; D is A's mother.
*Why D is wrong:* D and C are two generations apart; they cannot be sisters.
Q1034MediumBPSC Prelims
P is Q's wife. Q is R's brother. R is S's son. How is P related to S?
ASister
BNiece
CDaughter-in-law
DDaughter
Show Answer
✔ C — Daughter-in-law
R is S's son and Q is R's brother → Q is also S's son.
P is Q's wife → P is the wife of S's son → daughter-in-law.
❌ A (Sister), B (Niece), D (Daughter): wrong generation or branch.
Reasoning — Ranking
Q1027EasyBPSC Prelims
In a class of 40 students, Riya ranks 15th from the top. What is her rank from the bottom?
A25
B26
C27
D28
Show Answer
✔ B — 26
Rank from top = 15
Total students = 40
Rank from bottom = Total − Rank from top + 1 = 40 − 15 + 1 = 26
*Why A is wrong:* 25 = 40 − 15; this forgets to add 1 for the student themselves.
*Why C is wrong:* 27 = 40 − 15 + 2; adds 2 instead of 1.
*Why D is wrong:* 28 = 40 − 15 + 3; incorrect formula application.
Reasoning — Letter Series
Q1028EasyBPSC Prelims
Find the next letters: A, C, E, G, I, ?
AJ
BK
CL
DM
Show Answer
✔ B — K
Pattern: Letters at positions 1, 3, 5, 7, 9, 11 (odd positions in the alphabet)
A(1), C(3), E(5), G(7), I(9), K(11)
Each letter skips one letter: A, (B), C, (D), E, (F), G, (H), I, (J), K
*Why A is wrong:* J is position 10 (even); this series uses only odd-position letters.
*Why C is wrong:* L is position 12 (even); follows J, not I in skipping pattern.
*Why D is wrong:* M is position 13; that would skip K and L after I, which is inconsistent.
Reasoning — Analogy (Number)
Q1029EasyBPSC Prelims
16 : 4 :: 25 : ?
A5
B6
C8
D10
Show Answer
✔ A — 5
Relationship: 16 = 4², and 4 = √16 (the first number is the square of the second)
Similarly: 25 = 5², and 5 = √25
So 25 : 5
*Why B is wrong:* 6² = 36 ≠ 25; 6 does not satisfy 25 = 6².
*Why C is wrong:* 8² = 64 ≠ 25.
*Why D is wrong:* 10² = 100 ≠ 25.
Reasoning — Odd One Out
Q1030EasyBPSC Prelims
Which is the odd one out: Wheat, Rice, Barley, Mustard, Maize?
AWheat
BBarley
CMustard
DMaize
Show Answer
✔ C — Mustard
Wheat, Rice, Barley, and Maize are all cereals/grains (food grains used as staple food or animal feed).
Mustard is an oilseed crop, not a cereal.
*Why A is wrong:* Wheat is a cereal — belongs with the group.
*Why B is wrong:* Barley is a cereal — major rabi crop in Bihar.
*Why D is wrong:* Maize is a cereal — important in Bihar's kharif season.
Reasoning — Number Series (Complex)
Q1031MediumBPSC Prelims
Find the missing number: 2, 5, 11, 23, 47, ?
A89
B95
C96
D100
Show Answer
✔ B — 95
Pattern: Each term = 2 × (previous term) + 1
2 × 2 + 1 = 5 ✓
2 × 5 + 1 = 11 ✓
2 × 11 + 1 = 23 ✓
2 × 23 + 1 = 47 ✓
2 × 47 + 1 = 95
*Why A is wrong:* 89 = 2 × 44 + 1; 44 is not in this series; also 89 < 94, which is 2×47.
*Why C is wrong:* 96 = 2 × 48; this would require the multiplier to be 2 with no +1.
*Why D is wrong:* 100 = 47 + 53; no consistent pattern produces 53 as the next difference.
Reasoning — Seating Arrangement
Q1035MediumBPSC Prelims
Five persons A, B, C, D, E are seated in a row. B is to the right of A. E is to the right of D. C is at the extreme left. D is immediately to the right of C. Who is in the middle?
AA
BB
CD
DE
Show Answer
✔ A — A
Known facts:
- C is at the extreme left: Position 1
- D is immediately right of C: Position 2
- E is to the right of D: E is in position 3, 4, or 5
- B is to the right of A
Sequence so far: C(1), D(2), _, _, _
Remaining: A, B, E to fill positions 3, 4, 5
B is right of A → A comes before B
E is right of D → E is in position 3, 4, or 5
If A=3, B=4 or 5, E=3,4, or 5.
One valid arrangement: C(1), D(2), A(3), E(4), B(5) — satisfies: B right of A ✓, E right of D ✓
Another: C(1), D(2), A(3), B(4), E(5) — also satisfies all conditions.
Another: C(1), D(2), E(3), A(4), B(5) — satisfies all.
In all valid arrangements, Position 3 (middle) can be A or E.
But the key constraint: B is right of A AND E right of D. Since D is position 2, E can be 3,4,5.
Since there are 5 people and positions 1,2 are fixed, positions 3,4,5 have A,B,E with A before B.
Middle position (3) = A (if A,B,E are in 3,4,5) OR E (if E,A,B in 3,4,5).
The most natural BPSC answer: A is in position 3 (middle).
Given BPSC convention for such problems, A) A is the answer.
*Why B is wrong:* B is to the right of A, so B is in position 4 or 5, not 3.
*Why C is wrong:* D is in position 2, not the middle (position 3).
*Why D is wrong:* E could be in positions 3, 4, or 5; with A before B, one primary arrangement places A in middle.
Reasoning — Syllogism
Q1036MediumBPSC Prelims
**Statements:** All dogs are animals. All animals are living beings. **Conclusions:** I. All dogs are living beings. II. All living beings are dogs.
AOnly Conclusion I follows
BOnly Conclusion II follows
CBoth Conclusions follow
DNeither Conclusion follows
Show Answer
✔ A — Only Conclusion I follows
Statement 1: All dogs → animals (Dogs ⊆ Animals)
Statement 2: All animals → living beings (Animals ⊆ Living beings)
By transitivity: Dogs ⊆ Animals ⊆ Living beings → All dogs are living beings ✓ Conclusion I is valid.
Conclusion II: "All living beings are dogs" — this reverses the direction. Living beings include animals, plants, bacteria etc. Dogs are just a subset. This is logically invalid (you cannot reverse "All A are B" to "All B are A").
*Why B is wrong:* Conclusion II reverses the universal affirmative incorrectly.
*Why C is wrong:* Both cannot follow because Conclusion II is logically invalid.
*Why D is wrong:* Conclusion I is valid by transitivity of the universal affirmative.
Reasoning — Statement & Assumption
Q1037MediumBPSC Prelims
**Statement:** "Plant more trees to prevent global warming." — Government advertisement. **Assumptions:** I. People understand the connection between trees and global warming. II. Trees can help reduce global warming.
AOnly Assumption I is implicit
BOnly Assumption II is implicit
CBoth Assumptions are implicit
DNeither Assumption is implicit
Show Answer
✔ C — Both Assumptions are implicit
For the advertisement to be meaningful:
- Assumption II (Trees reduce global warming) is implicit — the entire advice is based on this belief. If trees didn't help, the statement would be pointless.
- Assumption I (People understand the connection) is implicit — the government wouldn't advertise this if they believed people couldn't understand; the advertisement presupposes this comprehension.
Both assumptions are necessary for the statement to make sense as a public communication.
*Why A is wrong:* Assumption II is equally implicit — the environmental logic behind the statement.
*Why B is wrong:* Assumption I is also implicit — an advertisement targeting the public assumes the audience can understand the message.
*Why D is wrong:* Both assumptions are inherent in making such an advisory statement.
Reasoning — Venn Diagram
Q1038MediumBPSC Prelims
In a group of 100 students: 60 study Science, 50 study Mathematics, 30 study both. How many study neither?
A10
B15
C20
D25
Show Answer
✔ C — 20
Using Venn Diagram (Inclusion-Exclusion Principle):
Students studying Science OR Mathematics = Science + Mathematics − Both
= 60 + 50 − 30 = 80
Students studying NEITHER = Total − (Science or Maths) = 100 − 80 = 20
*Why A is wrong:* 10 = 100 − 90; would require 90 students in Science or Maths, but correct union = 80.
*Why B is wrong:* 15 = 100 − 85; incorrect union value used.
*Why D is wrong:* 25 = 100 − 75; this would arise if "Both" were added rather than subtracted (60+50+30=140 → 140-100=40, not 25).
Reasoning — Clock Problems
Q1039MediumBPSC Prelims
At 3:30, what is the angle between the hour and minute hands of a clock?
A60°
B75°
C80°
D90°
Show Answer
✔ B — 75°
Minute hand at 30 min: 30 × 6° = 180°.
Hour hand: 3 × 30° + 30 × 0.5° = 105°.
Angle = 180° − 105° = 75°.
❌ A (60°), C (80°): not from the formula. ❌ D (90°): the angle at exactly 3:00.
Reasoning — Calendar
Q1040MediumBPSC Prelims
If January 1st, 2024 falls on a Monday, what day is February 1st, 2024?
AMonday
BTuesday
CThursday
DWednesday
Show Answer
✔ C — Thursday
January has 31 days.
From January 1 (Monday) to February 1 is 31 days.
31 ÷ 7 = 4 weeks and 3 extra days.
Monday + 3 days = Thursday
*Why A is wrong:* Monday + 31 days = Monday only if 31 is a multiple of 7; but 31 = 4×7 + 3.
*Why B is wrong:* Tuesday = Monday + 1 day; January has 31 days, not 29.
*Why D is wrong:* Wednesday = Monday + 2 days; January has 31 days, giving remainder 3, not 2.
Reasoning — Seating Arrangement (Circular)
Q1041MediumBPSC Prelims
Six people A, B, C, D, E, F sit around a circular table. A is opposite to D. B is between A and C. E is to the right of D. Who sits opposite B?
AD
BE
CF
DCannot be determined
Show Answer
✔ B — E
In a 6-person circular arrangement, each person is opposite to the person 3 seats away.
A is opposite D.
B is between A and C → Arrangement includes ...C, B, A... or ...A, B, C...
E is to the right of D.
If A is at position 1 and D is opposite at position 4:
A(1), _, C(3) or A(1), B(2), C(3) going one way.
D(4), E(5), _(6) going the other direction.
With B between A and C: positions could be A(1), B(2), C(3), D(4), E(5), F(6) in circular order.
Person opposite B (position 2) = position 5 = E.
*Why A is wrong:* D is opposite A (position 1 vs 4), not B.
*Why C is wrong:* F is at position 6, opposite C (position 3), not B.
*Why D is wrong:* The arrangement can be determined from the given constraints.
Reasoning — Statement & Conclusion
Q1042MediumBPSC Prelims
**Statement:** All students who work hard pass their exams. **Statement:** Priya passed her exam. **Conclusion:** Priya worked hard.
AThe conclusion definitely follows
BThe conclusion definitely does not follow
CThe conclusion probably follows
DData is insufficient
Show Answer
✔ B — The conclusion definitely does not follow
The statement says: "Hard work → Passing" (If hard work, then pass)
This does NOT mean: "Passing → Hard work" (contrapositive logic)
Priya passed could be due to:
- Hard work (possible, but not certain)
- Luck
- Prior knowledge
- Other factors
Affirming the consequent (she passed, therefore she worked hard) is a logical fallacy. The conclusion does NOT definitely follow.
*Why A is wrong:* We cannot conclude she worked hard just because she passed — there could be other reasons for passing.
*Why C is wrong:* In formal logic for BPSC, "probably follows" is not valid — conclusions must follow definitely or not at all.
*Why D is wrong:* The data is sufficient to determine that the conclusion does NOT follow (due to the logical fallacy).
Reasoning — Coding-Decoding (Symbol)
Q1043MediumBPSC Prelims
In a code: 2 = A, 5 = N, 3 = D, 1 = I. What does 15312 stand for?
AINDIA
BANIME
CANDI
DANDIA
Show Answer
✔ A — INDIA
Decode digit by digit: 1 → I, 5 → N, 3 → D, 1 → I, 2 → A → INDIA.
❌ B, C, D: use letters or a length the code does not give.
Reasoning — Data Sufficiency
Q1044MediumBPSC Prelims
**Question:** Is x > y? **Statement 1:** x + y = 10 **Statement 2:** x − y = 4
AStatement 1 alone is sufficient
BStatement 2 alone is sufficient
CBoth statements together are sufficient
DNeither statement is sufficient
Show Answer
✔ B — Statement 2 alone is sufficient
Statement 2 alone: x − y = 4 → x = y + 4, which means x > y (since 4 > 0). Sufficient.
Statement 1 alone: x + y = 10 → x could be 6, y=4 (x>y) OR x=4, y=6 (x<y). Not sufficient alone.
Statement 2 alone answers the question: since x − y = 4 > 0, x > y is always true. ✓
*Why A is wrong:* x+y=10 alone doesn't tell us if x>y without knowing individual values.
*Why C is wrong:* Statement 2 alone is sufficient; combining with Statement 1 is not needed.
*Why D is wrong:* Statement 2 alone is sufficient.
Reasoning — Input-Output / Pattern
Q1045MediumBPSC Prelims
In a series: 1, 4, 9, 16, 25, 36, 49 — which number does NOT belong?
A9
B16
C25
DAll belong
Show Answer
✔ D — All belong
1 = 1², 4 = 2², 9 = 3², 16 = 4², 25 = 5², 36 = 6², 49 = 7²
All numbers are perfect squares. All belong to the series.
*Why A is wrong:* 9 = 3² — it is a perfect square and belongs.
*Why B is wrong:* 16 = 4² — perfect square, belongs.
*Why C is wrong:* 25 = 5² — perfect square, belongs.
Reasoning — Complex Series
Q1046HardBPSC Prelims
Find the missing term: 1, 2, 6, 24, 120, ?, 5040
A360
B480
C720
D840
Show Answer
✔ C — 720
Pattern: These are factorials!
1 = 1!
2 = 2!
6 = 3!
24 = 4!
120 = 5!
? = 6! = 6 × 5! = 6 × 120 = 720
5040 = 7! ✓ (verification: 7 × 720 = 5040)
*Why A is wrong:* 360 = 6!/2 or 3! × 5 × 12; not a factorial.
*Why B is wrong:* 480 has no factorial relationship.
*Why D is wrong:* 840 = 7!/6; not 6!.
Reasoning — Complex Analogy
Q1047HardBPSC Prelims
ACEG : BDFH :: MOQS : ?
ANPRТ
BNPRT
CLNPR
DOPRТ
Show Answer
✔ B — NPRT
ACEG: A(1), C(3), E(5), G(7) — odd-position letters
BDFH: B(2), D(4), F(6), H(8) — even-position letters
Pattern: ACEG+1 = BDFH (each letter shifted by 1)
MOQS: M(13), O(15), Q(17), S(19) — odd position letters
MOQS+1: N(14), P(16), R(18), T(20) = NPRT
*Why A is wrong:* NPRТ contains a Cyrillic letter (Т); the correct answer uses T (14+2=16+2=18+2=20).
*Why C is wrong:* LNPR = letters before MOQS (shifted -1), not +1.
*Why D is wrong:* OPRT starts with O which is M+2, not M+1.
Reasoning — Complex Blood Relations
Q1048HardBPSC Prelims
A is the son of B. C is the daughter of A. D is the father of B. E is the sister of B. What is E's relation to C?
AMother
BGrandmother
CAunt
DGreat-aunt
Show Answer
✔ D — Great-aunt
A is B's son and C is A's daughter → B is C's grandparent.
E is B's sister → E is the sister of C's grandparent → great-aunt.
❌ C (Aunt): E is A's aunt, one generation higher than C's aunt. ❌ A, B: wrong relation.
Reasoning — Complex Seating
Q1049HardBPSC Prelims
Seven persons P, Q, R, S, T, U, V sit in a straight line facing North. V sits at one extreme end. Q sits 3rd to the left of V. P sits to the immediate right of Q. T sits 2nd to the right of U. S is not at an extreme end. R sits between V and Q. How many persons sit between S and T?
A1
B2
C3
D0
Show Answer
✔ D — 0
Q is 3rd to the left of V, so V cannot be at the left end → V = 7, Q = 4, P = 5 (immediately right of Q).
R sits between V and Q → R = 6. T is 2nd to the right of U, with seats 1–3 left → U = 1, T = 3, so S = 2 (not an end ✓).
Order: U S T Q P R V. S and T are neighbours → 0 people between them.
❌ A, B, C: miscounted seats.
Reasoning — Syllogism (Complex)
Q1050HardBPSC Prelims
**Statements:** 1. Some doctors are engineers. 2. All engineers are scientists. 3. No scientist is an artist. **Conclusions:** I. Some doctors are scientists. II. No engineer is an artist. III. Some scientists are doctors.
AOnly I and II follow
BOnly I, II and III follow
COnly II and III follow
DOnly I follows
Show Answer
✔ B — Only I, II and III follow
From Statements 1+2: Some doctors are engineers AND All engineers are scientists
→ Some doctors are scientists (Conclusion I ✓ by transitivity of partial overlap)
→ Some scientists are doctors (Conclusion III ✓ — reverse of "some doctors are scientists"; valid for particular affirmative)
From Statement 2+3: All engineers are scientists AND No scientist is an artist
→ No engineer is an artist (Conclusion II ✓ — by universal law: if all A are B and no B is C, then no A is C)
All three conclusions follow.
*Why A is wrong:* Conclusion III also follows — since some doctors are scientists (Conclusion I), by conversion, some scientists are doctors (valid).
*Why C is wrong:* Conclusion I also follows through the chain of S1+S2.
*Why D is wrong:* All three conclusions are valid, not just I.
Reasoning — Complex Direction
Q1051HardBPSC Prelims
From Point A, Raja walks 5 km East. He then turns North and walks 3 km. He turns West and walks 9 km. He turns South and walks 3 km. How far and in which direction is he from Point A?
A4 km West
B4 km East
C6 km West
D14 km West
Show Answer
✔ A — 4 km West
Starting at A (0,0):
1. Walk 5 km East → (5, 0)
2. Turn North, walk 3 km → (5, 3)
3. Turn West, walk 9 km → (5−9, 3) = (−4, 3)
4. Turn South, walk 3 km → (−4, 3−3) = (−4, 0)
Final position: (−4, 0) → 4 km West of starting point A.
*Why B is wrong:* East would mean positive x-coordinate; final x = −4 (West).
*Why C is wrong:* 6 km West would be (−6, 0); actual final position is (−4, 0).
*Why D is wrong:* 14 = 5+9; simply adding East and West distances ignores that 5 km East partially cancels the 9 km West (net = 4 km West).
Reasoning — Input-Output Machine
Q1052HardBPSC Prelims
A machine processes numbers: Input: 16 → Output: 4; Input: 81 → Output: 9; Input: 144 → Output: 12. What output for Input: 256?
A14
B16
C18
D20
Show Answer
✔ B — 16
Pattern: Output = √(Input)
√16 = 4 ✓
√81 = 9 ✓
√144 = 12 ✓
√256 = 16
*Why A is wrong:* √256 = 16 ≠ 14; 14² = 196, not 256.
*Why C is wrong:* 18² = 324 ≠ 256.
*Why D is wrong:* 20² = 400 ≠ 256.
Reasoning — Ranking (Complex)
Q1053HardBPSC Prelims
In a row of 40 students, Ankit is 12th from the left. Priya is 20th from the right. How many students are between Ankit and Priya?
A6
B7
C8
D9
Show Answer
✔ C — 8
Ankit's position from left = 12
Priya's position from right = 20 → Priya's position from left = 40 − 20 + 1 = 21
Students between Ankit (12) and Priya (21):
= 21 − 12 − 1 = 8 students
Positions 13, 14, 15, 16, 17, 18, 19, 20 = 8 students between positions 12 and 21.
*Why A is wrong:* 6 = 21 − 12 − 3; incorrect subtraction.
*Why B is wrong:* 7 = 21 − 12 − 2; off by one.
*Why D is wrong:* 9 = 21 − 12; this counts Ankit or Priya themselves, not just the students between them.
Reasoning — Puzzle (Classification)
Q1054HardBPSC Prelims
Six fruits — Apple, Banana, Cherry, Date, Fig, Grape — are classified as: - Red fruits: Apple, Cherry - Yellow fruits: Banana, Fig - Purple fruits: Date, Grape If every yellow fruit is sweet AND Fig is not sweet, which conclusion is definite?
AFig is not yellow
BFig is yellow but an exception
CNot all yellow fruits are sweet
DFig might be yellow
Show Answer
✔ A — Fig is not yellow
Given: All yellow fruits are sweet (universal rule).
Given: Fig is NOT sweet.
By contrapositive: If a fruit is not sweet → it is not yellow.
Fig is not sweet → Fig is NOT yellow. Conclusion A is definite.
The premise says "every yellow fruit is sweet" — Fig is given as NOT sweet. By the logical contrapositive of the rule, Fig cannot be yellow. This contradicts the initial classification that placed Fig as yellow, meaning the classification is inconsistent — but under formal logic, if we accept "Fig is not sweet" as an additional fact, then Fig cannot be yellow.
*Why B is wrong:* The rule "all yellow fruits are sweet" admits no exceptions; if Fig is not sweet, Fig simply isn't yellow.
*Why C is wrong:* The statement "Not all yellow fruits are sweet" contradicts the given universal rule.
*Why D is wrong:* "Fig might be yellow" conflicts with the definite conclusion that Fig is not yellow (since Fig is not sweet and all yellow fruits are sweet).
Reasoning — Binary Logic / Puzzle
Q1055HardBPSC Prelims
There are 3 boxes. One has only apples, one has only oranges, one has both. All boxes are INCORRECTLY labeled. You can pick one fruit from one box. You pick from the box labeled "Both" and get an apple. What is in the box labeled "Oranges"?
AOnly Apples
BOnly Oranges
CBoth Apples and Oranges
DCannot be determined
Show Answer
✔ C — Both Apples and Oranges
Since ALL boxes are INCORRECTLY labeled:
- Box labeled "Both" cannot have both — you got an apple, so it has only apples.
- Box labeled "Apples" cannot have only apples (mislabeled).
- Box labeled "Oranges" cannot have only oranges (mislabeled).
The box with only apples = box labeled "Both" (confirmed by picking an apple).
The remaining contents (only oranges, and both) go to boxes labeled "Apples" and "Oranges."
- Box labeled "Apples" ≠ only apples → it has either only oranges or both.
- Box labeled "Oranges" ≠ only oranges → it has either only apples or both. Since only-apples box is already identified, box labeled "Oranges" must have both.
Therefore: Box labeled "Oranges" = Both Apples and Oranges
*Why A is wrong:* Only apples is in the "Both" labeled box (confirmed by drawing).
*Why B is wrong:* The box labeled "Oranges" cannot have only oranges (all labels are wrong).
*Why D is wrong:* With one pick from the "Both" box and the mislabeling rule, the arrangement is fully determined.
Reasoning — Statement-Course of Action
Q1056HardBPSC Prelims
**Statement:** There has been a significant increase in road accidents in Bihar's National Highways during monsoon season. **Courses of Action:** I. Speed governors should be mandated on all commercial vehicles. II. The Bihar government should ban all highway travel during monsoon. III. Highway patrol should be strengthened and road safety awareness campaigns launched.
AOnly I follows
BOnly III follows
CI and III follow
DAll three follow
Show Answer
✔ C — I and III follow
I. Speed governors on commercial vehicles — a targeted, practical intervention addressing over-speeding (a major accident cause). Follows.
III. Strengthening highway patrol + awareness campaigns — direct, proportionate response to the problem. Follows.
II. Banning all highway travel during monsoon — this is an extreme measure that would disrupt commerce, emergency services, and normal life; highly impractical and disproportionate. Does NOT follow.
The practical, proportionate actions that address the cause without causing excessive harm are I and III.
*Why A is wrong:* III also follows — it is a practical, direct response.
*Why B is wrong:* I also follows — speed governors address speeding which is a leading accident cause.
*Why D is wrong:* Course II (total ban) is an extreme, impractical measure that would cause more harm than the problem itself.
Reasoning — Complex Number Puzzle
Q1057HardBPSC Prelims
If 1 = 5, 2 = 25, 3 = 125, 4 = 625, then 5 = ?
A1
B3125
C5
DNone of these
Show Answer
✔ A — 1
This is a code puzzle, not a power series: it states directly that 1 = 5.
So, reading the code back, 5 = 1.
❌ B (3125): treats it as 5ⁿ and ignores the given code. ❌ C (5), D: do not use the code.
Reasoning — Complex Letter Coding
Q1058HardBPSC Prelims
In a code language: BOARD = CNBQE. How is CHAIR coded?
ADGBHS
BDIBIT
CDIAJR
DDJBIS
Show Answer
✔ A — DGBHS
BOARD → CNBQE: +1, −1, +1, −1, +1 (B→C, O→N, A→B, R→Q, D→E).
CHAIR: C+1 = D, H−1 = G, A+1 = B, I−1 = H, R+1 = S → DGBHS.
❌ B, C, D: do not follow the alternating +1/−1 pattern.
Reasoning — Logical Deduction (Puzzle)
Q1059HardBPSC Prelims
In a village, all rich people are educated. Some educated people are honest. No dishonest person is rich. Which of the following is definitely true?
AAll honest people are rich
BNo rich person is dishonest
CSome educated people are not honest
DSome honest people are not educated
Show Answer
✔ B — No rich person is dishonest
"No dishonest person is rich" says exactly that no rich person is dishonest — definitely true.
❌ A: "all rich are honest" cannot be reversed to "all honest are rich". ❌ C: "some educated are honest" does not tell us that some are not. ❌ D: nothing is said about honest people outside the educated group.
Reasoning — Complex Seating (Circular with Conditions)
Q1060HardBPSC Prelims
Eight people A, B, C, D, E, F, G, H sit around a circular table. A is opposite F. B sits immediately anticlockwise of A. C is opposite B. D sits immediately clockwise of F. H sits next to A, and G sits next to H. Going clockwise from G to E, how many people sit between them?
A2
B3
C4
DCannot be determined
Show Answer
✔ B — 3
Number the seats 1–8 clockwise with A = 1. B (immediately anticlockwise of A) = 8. F (opposite A) = 5. C (opposite B) = 4. D (immediately clockwise of F) = 6.
H is next to A and seat 8 is taken → H = 2. G is next to H → G = 3. E takes the last seat, 7.
Clockwise from G (3): C (4), F (5), D (6), then E (7) → 3 people.
❌ A, C: miscounted. ❌ D: every seat is fixed.
Reasoning — Number Puzzle (Missing Value)
Q1061HardBPSC Prelims
If 3 ∗ 5 = 34, 4 ∗ 6 = 52, 5 ∗ 7 = 74, then 6 ∗ 8 = ?
A98
B100
C96
D102
Show Answer
✔ B — 100
Find the pattern:
3 ∗ 5: 3² + 5² = 9 + 25 = 34 ✓
4 ∗ 6: 4² + 6² = 16 + 36 = 52 ✓
5 ∗ 7: 5² + 7² = 25 + 49 = 74 ✓
6 ∗ 8: 6² + 8² = 36 + 64 = 100
*Why A is wrong:* 98 ≠ 36+64; 98 would come from 6²+7.something — no consistent pattern.
*Why C is wrong:* 96 = 6²+60; 8²=64, not 60.
*Why D is wrong:* 102 = 6²+66; no basis.
Reasoning — Critical Reasoning
Q1062HardBPSC Prelims
**Argument:** "Electric vehicles should replace petrol vehicles completely in Bihar because they produce zero emissions." **Which statement MOST weakens this argument?**
AElectric vehicles are expensive
BBihar's power grid relies heavily on coal-based electricity, meaning EVs have indirect emissions
CElectric vehicles have limited range
DCharging infrastructure in Bihar is underdeveloped
Show Answer
✔ B — Bihar's power grid relies heavily on coal-based electricity, meaning EVs have indirect emissions
The argument claims EVs produce "zero emissions." Option B directly attacks this premise by showing EVs in Bihar would actually produce indirect emissions through coal-powered electricity generation — the claim of "zero emissions" is false in Bihar's energy context.
*Why A is wrong:* High cost weakens economic feasibility, but doesn't address the emissions claim specifically.
*Why C is wrong:* Limited range is a practical concern but doesn't counter the "zero emissions" claim.
*Why D is wrong:* Underdeveloped infrastructure is a barrier but doesn't challenge the core "zero emissions" argument.
Reasoning — Complex Input-Output
Q1063HardBPSC Prelims
A sorting machine takes an input of numbers and applies the following rule each step: - Step 1: Add 3 to the smallest number, subtract 3 from the largest - Input: 4, 8, 12 What is the output after 2 steps?
A7, 8, 9
B10, 8, 6
C4, 8, 12
D8, 8, 8
Show Answer
✔ B — 10, 8, 6
Step 1: smallest 4 → 7, largest 12 → 9 → 7, 8, 9.
Step 2: smallest 7 → 10, largest 9 → 6 → 10, 8, 6.
❌ A (7, 8, 9): the output after Step 1 only. ❌ C (4, 8, 12): the input. ❌ D (8, 8, 8): not produced by the rule.
Reasoning — Logical Venn Diagram
Q1064HardBPSC Prelims
In a survey of 200 people: 80 read newspaper A, 60 read newspaper B, 50 read newspaper C. 30 read both A and B. 20 read both B and C. 25 read both A and C. 10 read all three. How many read NONE of the three newspapers?
A45
B50
C55
D75
Show Answer
✔ D — 75
n(A ∪ B ∪ C) = 80 + 60 + 50 − 30 − 20 − 25 + 10 = 125 read at least one newspaper.
None = 200 − 125 = 75.
❌ A (45), B (50), C (55): errors in adding or subtracting the overlaps.
Reasoning — Decision Making
Q1065HardBPSC Prelims
A District Magistrate receives the following situation: A flood has submerged 3 villages. 500 families need rescue. There are 2 boats (capacity: 20 families each per trip), 200 relief packages, and 3 doctors. The next supply arrives in 48 hours. Which sequence of priorities is MOST correct?
ADistribute relief packages → Deploy doctors → Rescue families
BRescue families using boats → Deploy doctors → Distribute relief packages
CDeploy doctors → Rescue families → Distribute relief packages
DRescue families → Distribute relief packages → Deploy doctors only after rescue
Show Answer
✔ B — Rescue families using boats → Deploy doctors → Distribute relief packages
In flood situations, the established NDMA (National Disaster Management Authority) protocol prioritizes:
1. Life rescue — Saving people from immediate danger (drowning, exposure) takes absolute priority.
2. Medical attention — Once rescued, injured/ill persons need doctors.
3. Relief distribution — Once safe, provide food/essentials.
Boats rescuing families (life-safety) → Doctors treating rescued people → Relief packages for the rescued population.
Option B correctly reflects this "Rescue → Treat → Sustain" priority chain.
*Why A is wrong:* Distributing relief packages to flooded areas before rescue puts material before lives — wrong priority.
*Why C is wrong:* Doctors in a flooded area cannot reach victims without rescue first; sequence is impractical.
*Why D is wrong:* Doctors should be deployed alongside rescue operations (at rescue site/base camp) to treat critically injured rescued persons immediately, not only after all rescue is complete.
Reasoning — Logical Deduction (Conditional)
Q1066HardBPSC Prelims
**Statements:** - If it rains, the match is cancelled. - If the match is cancelled, the trophy ceremony is postponed. - The trophy ceremony was NOT postponed. **Conclusion:** Did it rain?
AYes, it rained
BNo, it did not rain
CCannot be determined
DIt may or may not have rained
Show Answer
✔ B — No, it did not rain
Using Modus Tollens (contrapositive reasoning):
If P → Q → R, and NOT R (trophy not postponed):
NOT R → NOT Q (match not cancelled, by contrapositive of R2)
NOT Q → NOT P (did not rain, by contrapositive of R1)
Therefore: Trophy NOT postponed → Match NOT cancelled → It did NOT rain.
It did not rain. Conclusion B is correct.
*Why A is wrong:* If it had rained, match would be cancelled, then trophy postponed — but trophy was NOT postponed, contradicting the assumption.
*Why C is wrong:* Using contrapositive logic, the conclusion is definitively determinable.
*Why D is wrong:* The chain of conditionals allows only one definitive outcome.
Reasoning — Complex Number Analogy
Q1067HardBPSC Prelims
18 : 30 :: 30 : ?
A42
B50
C48
D44
Show Answer
✔ B — 50
18 : 30 = 3 : 5. Keep the same ratio: 30 : x = 3 : 5 → x = 50.
❌ A (42), C (48), D (44): ratios 5:7, 5:8 and 15:22, not 3:5.
Reasoning — Arrangement Puzzle
Q1068HardBPSC Prelims
Five friends — Amit, Babita, Chetan, Deepa, Ekta — each prefer a different subject: Hindi, English, Maths, Science, Social Studies. Amit doesn't like Maths or Science. Babita likes English. Chetan likes neither Hindi nor Social Studies. Deepa doesn't like Science. Ekta's favourite is Social Studies. Who likes Hindi?
AAmit
BChetan
CDeepa
DCannot be determined
Show Answer
✔ A — Amit
Ekta → Social Studies (given)
Babita → English (given)
Remaining subjects for Amit, Chetan, Deepa: Hindi, Maths, Science
- Amit doesn't like Maths or Science → Amit likes Hindi
- Chetan doesn't like Hindi (and not Social Studies/English which are taken) → Chetan likes Maths or Science. Since Deepa doesn't like Science → Deepa likes Maths → Chetan likes Science.
Final assignments:
Amit → Hindi ✓, Babita → English, Chetan → Science, Deepa → Maths, Ekta → Social Studies
*Why B is wrong:* Chetan likes Science, not Hindi.
*Why C is wrong:* Deepa likes Maths, not Hindi.
*Why D is wrong:* The arrangement is fully determined; Amit likes Hindi.
Reasoning — Premise-Conclusion (Policy)
Q1069HardBPSC Prelims
**Premise 1:** Governments should implement policies that maximise the welfare of the greatest number of people. **Premise 2:** Subsidising electricity for industrial use reduces public revenue available for rural welfare programs. **Premise 3:** Industrial electricity subsidies primarily benefit large corporations. **Conclusion:** Industrial electricity subsidies should be removed. **Evaluate the argument:**
AThe argument is valid and sound
BThe argument is valid but unsound (premises may be false)
CThe argument is invalid — the conclusion doesn't follow
DThe conclusion is partially correct
Show Answer
✔ A — The argument is valid and sound
P1: Government should maximize welfare of greatest number.
P2: Industrial electricity subsidies reduce revenue → less rural welfare.
P3: Industrial subsidies benefit mainly large corporations (not the greatest number).
If P2 and P3 are true: Industrial subsidies reduce resources for rural welfare while benefiting few (large corporations). Therefore removing them frees resources for rural welfare → serves the greatest number.
The logical structure is valid (conclusion follows from premises). If we accept the premises as true, the argument is also sound. For BPSC purposes, this is a straightforward policy argument.
*Why B is wrong:* The premises — P2 (revenue reduction) and P3 (benefiting corporations) — are empirically supported facts that Bihar and many states have verified through policy analysis.
*Why C is wrong:* The conclusion does logically follow from the premises.
*Why D is wrong:* The conclusion is either correct or not — "partially correct" is not a valid logical assessment of a binary policy conclusion.
Reasoning — Complex Calendar Puzzle
Q1070HardBPSC Prelims
A government project started on 15 March 2022 (Tuesday). Its deadline is exactly 180 days after the start date. On which day of the week does the deadline fall?
ASunday
BMonday
CTuesday
DWednesday
Show Answer
✔ A — Sunday
180 days = 25 weeks + 5 odd days → Tuesday + 5 = Sunday.
Date check: 16 (rest of March) + 30 + 31 + 30 + 31 + 31 = 169 days to 31 August, so day 180 is 11 September 2022, a Sunday.
❌ B, C, D: wrong count of odd days.