Aptitude

Question: 8, 7, 11, 12, 14, 17, 17, 22, (….)

[A].

27

[B].

20

[C].

22

[D].

24

Answer: Option B

Explanation:

There are two series (8, 11, 14, 17, 20) and (7, 12, 17, 22) increasing by 3 and 5 respectively.

Question:
2, 4, 12, 48, 240, (….)

[A].

960

[B].

1440

[C].

1080

[D].

1920

Answer: Option B

Explanation:

Go on multiplying the given numbers by 2, 3, 4, 5, 6.

So, the correct next number is 1440.

Question:
7, 26, 63, 124, 215, 342, (….)

[A].

481

[B].

511

[C].

391

[D].

421

Answer: Option B

Explanation:

Numbers are (23 – 1), (33 – 1), (43 – 1), (53 – 1), (63 – 1), (73 – 1) etc.

So, the next number is (83 – 1) = (512 – 1) = 511.

Question: 8, 24, 12, 36, 18, 54, (….)
[A].

27

[B].

108

[C].

68

[D].

72

Answer: Option A

Explanation:

Numbers are alternatively multiplied by 3 and divided by 2.

So, the next number = 54 ÷ 2 = 27.

Question:
2, 6, 12, 20, 30, 42, 56, (….)

[A].

61

[B].

64

[C].

72

[D].

70

Answer: Option C

Explanation:

The pattern is 1 x 2, 2 x 3, 3 x 4, 4 x 5, 5 x 6, 6 x 7, 7 x 8.

So, the next number is 8 x 9 = 72.

Question:
15, 31, 63, 127, 255, (….)

[A].

513

[B].

511

[C].

517

[D].

523

Answer: Option B

Explanation:

Each number is double the preceding one plus 1.

So, the next number is (255 x 2) + 1 = 511.

Question:
3, 7, 6, 5, 9, 3, 12, 1, 15, (….)

[A].

18

[B].

13

[C].

-1

[D].

3

Answer: Option C

Explanation:

There are two series, beginning respectively with 3 and 7. In one 3 is added and in another 2 is subtracted.

The next number is 1 – 2 = -1.

Question:
16, 33, 65, 131, 261, (….)

[A].

523

[B].

521

[C].

613

[D].

721

Answer: Option A

Explanation:

Each number is twice the preceding one with 1 added or subtracted alternatively.

So, the next number is (2 x 261 + 1) = 523.

Question:
11, 13, 17, 19, 23, 29, 31, 37, 41, (….)

[A].

43

[B].

47

[C].

53

[D].

51

Answer: Option A

Explanation:

Numbers are all primes. The next prime is 43.

Question:
1, 8, 27, 64, 125, 216, (….)

[A].

354

[B].

343

[C].

392

[D].

245

Answer: Option B

Explanation:

Numbers are 13, 23, 33, 43, 53, 63.

So, the missing number is 73 = 343.