Mental Ability — Pack 09

Question 1

Complete: 3A, 6B, 9C, ?

Accepted Answer

12D — +3 in numbers, next letter. 12D.

Answer

11D

Answer

12E

Answer

11E

Question 2

Solve: 2x + 3 = 15:

Accepted Answer

6 — 2x = 12 → x = 6.

Answer

4

Answer

5

Answer

7

Question 3

Pipe fills 6 hrs, empty 9 hrs. Both open:

Accepted Answer

18 hrs — 1/6-1/9=1/18.

Answer

12 hrs

Answer

15 hrs

Answer

10 hrs

Question 4

Rama travelled 5 km east, turned right and travelled 3 km, turned left and travelled 2 km. Which direction is he facing?

Accepted Answer

East — East → (right) South → (left) East. He faces east.

Answer

North

Answer

South

Answer

West

Question 5

GP 2, 4, 8, 16: 10th term:

Accepted Answer

1024 — 2×2^9=1024.

Answer

512

Answer

2048

Answer

256

Question 6

A point (−3, 4) lies in which quadrant?

Accepted Answer

II — Quadrant II: x negative, y positive.

Answer

I

Answer

III

Answer

IV

Question 7

Series: 0, 3, 8, 15, 24, ?

Accepted Answer

35 — n²-1 starting n=1; 6²-1=35.

Answer

33

Answer

36

Answer

40

Question 8

In a right triangle, angles:

Accepted Answer

90°, other two sum 90° — One 90°.

Answer

180°

Answer

90° both

Answer

60°

Question 9

In a row, Anil is 11th from left, Akhil is 11th from right. After interchange, Akhil is 15th from right. How many boys in the row?

Accepted Answer

25 — After swap, Akhil is at Anil's old place. So Anil's old position = 15th from right. Anil 11th from left = 15th from right → total = 11+15-1 = 25.

Answer

22

Answer

26

Answer

18

Question 10

Which type of sampling involves dividing the population into distinct subgroups and selecting a random sample from each subgroup?

Accepted Answer

Stratified Sampling — Stratified sampling divides the population into homogeneous strata and samples from each.

Answer

Simple Random Sampling

Answer

Cluster Sampling

Answer

Convenience Sampling

Question 11

IP version 4 address format:

Accepted Answer

32-bit, 4 octets — ~4.3 billion addresses. IPv6: 128-bit (2^128 addresses). IPv4 exhaustion led to IPv6 adoption. Dual-stack transition.

Answer

64-bit

Answer

128-bit

Answer

8-bit

Question 12

Volume of a cube is 64 cm³. Its total surface area is:

Accepted Answer

96 cm² — Side = ³√64 = 4 cm. TSA = 6 × 16 = 96 cm².

Answer

8 cm²

Answer

32 cm²

Answer

64 cm²

Question 13

Complex number i² =

Accepted Answer

-1 — i = √-1. i³=-i, i⁴=1. Period 4 in powers.

Answer

0

Answer

1

Answer

√-1

Question 14

100, 50, 25, 12.5, ?

Accepted Answer

6.25 — Each ÷ 2. 12.5 ÷ 2 = 6.25.

Answer

5

Answer

6

Answer

7.5

Question 15

An aeroplane flies 600 km in 20 minutes. Speed of aeroplane:

Accepted Answer

1800 km/hr — Speed = 600 / (20/60) = 600 × 3 = 1800 km/hr.

Answer

1200 km/hr

Answer

1500 km/hr

Answer

2000 km/hr

Question 16

Number of subsets of a set with n elements:

Accepted Answer

2^n — Each element is in or out → 2 choices. Empty set counts. Number of proper subsets: 2^n - 1.

Answer

n

Answer

n²

Answer

n!

Question 17

What is the sum of two consecutive even numbers, the difference of whose squares is 100?

Accepted Answer

50 — Let numbers be n and n+2. (n+2)² − n² = 4n+4 = 100 → n=24. Sum = 24+26 = 50.

Answer

46

Answer

40

Answer

60

Question 18

If A = [[1,2],[3,4]], trace of A:

Accepted Answer

5 — Trace = sum of diagonal = 1 + 4 = 5. Invariant under similarity transformations.

Answer

4

Answer

10

Answer

1

Question 19

Shopkeeper marks 20% above CP, offers 10% disc. Profit%:

Accepted Answer

8% — 1.2×0.9=1.08.

Answer

10%

Answer

12%

Answer

5%

Question 20

Two dice thrown. Prob of sum < 5:

Accepted Answer

1/6 — Favourable outcomes: sum = 2 (1 way: 1+1), sum = 3 (2 ways: 1+2, 2+1), sum = 4 (3 ways: 1+3, 2+2, 3+1). Total favourable = 6. Total outcomes = 36. Probability = 6/36 = 1/6.

Answer

1/4

Answer

5/36

Answer

1/3

Question 21

In a parallelogram, opposite sides are:

Accepted Answer

Equal and parallel — Definition of parallelogram: both pairs of opposite sides parallel (and equal).

Answer

Perpendicular

Answer

Unequal

Answer

Curved

Question 22

A train 520 m long is running with a speed of 90 km/hr. In what time will it cross a bridge 130 m long?

Accepted Answer

26 second — Total distance = 520+130 = 650 m. Speed = 90 km/h = 25 m/s. Time = 650/25 = 26 seconds.

Answer

25 second

Answer

32 second

Answer

30 second

Question 23

12.5 + 12.3 minus you (12.5 ÷ 12.3) ratio (a:b form):

Accepted Answer

5:8 — OCR garbled; answer per standard key 5:8.

Answer

11:8

Answer

8:1

Answer

8:5

Question 24

Analogy: Doctor : Patient :: Lawyer : ?

Accepted Answer

Client — Lawyer serves client.

Answer

Judge

Answer

Court

Answer

Case

Question 25

If a letter is chosen randomly from the word MATHS, P(vowel) =

Accepted Answer

1/5 — M, A, T, H, S — only 'A' is a vowel out of 5. P = 1/5.

Answer

2/5

Answer

3/5

Answer

4/5

Mental Ability — Pack 09