Odd Man Out And Series

Question: 15, 16, 34, 105, 424, 2124, 12756
[A].

16

[B].

34

[C].

105

[D].

424

Answer: Option E

Explanation:

2nd term = (1st term) x 1 + 1 = 15 x 1 + 1 = 16.

3rd term = (2nd term) x 2 + 2 = 16 x 2 + 2 = 34.

4th term = (3th term) x 3 + 3 = 34 x 3 + 3 = 105.

5th term = (4th term) x 4 + 4 = 105 x 4 + 4 = 424

6th term = (5th term) x 5 + 5 = 424 x 5 + 5 = 2125

6th term should 2125 instead of 2124.

Question: 10, 26, 74, 218, 654, 1946, 5834

[A].

26

[B].

74

[C].

218

[D].

654

Answer: Option D

Explanation:

2nd term = (1st term) x 3 – 4 = 10 x 3 – 4 = 26.

3rd term = (2nd term) x 3 – 4 = 26 x 3 – 4 = 74.

4th term = (3th term) x 3 – 4 = 74 x 3 – 4 = 218.

5th term = (4th term) x 3 – 4 = 218 x 3 – 4 = 650.

5th term must be 650 instead of 654.

Question:
6, 12, 48, 100, 384, 768, 3072

[A].

768

[B].

384

[C].

100

[D].

48

Answer: Option C

Explanation:

Each even term of the series is obtained by multiplying the previous term by 2.

2nd term = (1st term) x 2 = 6 x 2 = 12

4th term = (3rd term) x 2 = 48 x 2 = 96.

6th term = (5th term) x 2 = 384 x 2 =768.

4th term should be 96 instead of 100.

Question: 196, 169, 144, 121, 100, 80, 64
[A].

169

[B].

144

[C].

121

[D].

100

Answer: Option E

Explanation:

Numbers must be (14)2, (13)2, (12)2, (11)2, (10)2, (9)2, (8)2.

So, 80 is wrong.

Question:
1, 3, 10, 21, 64, 129, 356, 777

[A].

10

[B].

21

[C].

64

[D].

129

Answer: Option E

Explanation:

A x 2 + 1, B x 3 + 1, C x 2 + 1, D x 3 + 1 and so on.

So, 356 is wrong.

Question:
3, 7, 15, 39, 63, 127, 255, 511

[A].

7

[B].

15

[C].

39

[D].

63

Answer: Option C

Explanation:

Go on multiplying 2 and adding 1 to get the next number.

So, 39 is wrong.

Question: 445, 221, 109, 46, 25, 11, 4
[A].

221

[B].

109

[C].

46

[D].

25

Answer: Option C

Explanation:

Go on subtracting 3 and dividing the result by 2 to obtain the next number.

Clearly, 46 is wrong.

Question: 2880, 480, 92, 24, 8, 4, 4

[A].

480

[B].

92

[C].

24

[D].

8

Answer: Option B

Explanation:

Go on dividing by 6, 5, 4, 3, 2, 1 respectively to obtain the next number.

Clearly, 92 is wrong.

Question:
19, 26, 33, 46, 59, 74, 91

[A].

26

[B].

33

[C].

46

[D].

59

Answer: Option B

Explanation:

Go on adding 7, 9, 11, 13, 15, 17 respectively to obtain the next number.

So, 33 is wrong. It must be 35

Question:
3, 7, 15, 27, 63, 127, 255

[A].

7

[B].

15

[C].

27

[D].

63

Answer: Option C

Explanation:

Go on multiplying the number by 2 and adding 1 to it to get the next number.

So, 27 is wrong.