1. Find out the wrong term: 325, 259, 202, 160, 127, 105, 94

a) 94

b) 127

c) 202

d) 259

Explanation: The correct pattern is - 66, - 55, - 44, - 33, - 22, - 11.

So, 202 is wrong and must be replaced by (259 - 55) i.e., 204.

2. Find out the wrong term: 3, 4, 10, 32, 136, 685, 4116

a) 10

b) 32

c) 136

d) 4116

Explanation: The correct pattern is × 1 + 1, × 2 + 2, × 3 + 3, × 4 + 4, ..........

So, 32 is wrong and must be replaced by (10 × 3 + 3) i.e., 33.

3. Find out the wrong term: 380, 188, 92, 48, 20, 8, 2

a) 8

b) 20

c) 48

d) 188

Explanation: The correct pattern is - 192, - 96, - 48, - 24, - 12, - 6.

So, 48 is wrong and must be replaced by (92 - 48) i.e., 44.

4. Find out the wrong term: 2, 6, 24, 96, 285, 568, 567

a) 6

b) 24

c) 285

d) 567

Explanation: The correct pattern is ×6 -6, ×5 -5, ×4 -4, ×3 -3, . . . . .

So, 24 is wrong and must be replaced by (6 × 5 - 5) i.e., 25

5. Find out the wrong term: 89, 78, 86, 80, 85, 82, 83

a) 83

b) 82

c) 86

d) 78

Explanation: The correct pattern is - 11, + 9, - 7, + 5, - 3 + 1.

So, 86 is wrong and must be replaced by (78 + 9) i.e., 87.

6. In a given series one term is wrong or missing term: 1, 2, 5, 10, 17, 28

a) 30

b) 28

c) 27

d) 17

Explanation: The correct sequence is + 1, + 3, + 5, + 7, + 9.

So, 28 is wrong and must be replaced by (17 + 9) i.e., 26.

7. In a given series one term is wrong or missing term: 0, 3, 8, 15, 24, 33

a) 8

b) 15

c) 26

d) 33

Explanation: The correct pattern is + 3, + 5, + 7, + 9, + 11.

So, 33 is wrong and must be replaced by (24 + 11) i.e., 35.

8. In a given series one term is wrong or missing term: 2, 3, 5, 8, 13, 34

a) 21

b) 25

c) 29

d) 34

Explanation: Clearly, each term of the series is the sum of the preceding two terms.

Now, 8 + 13 = 21 and 13 + 21 = 34.

So, the term 21 is missing.

9. In a given series one term is wrong or missing term: 1, 5, 11, 19, 29, 55

a) 55

b) 41

c) 29

d) 19

Explanation: The correct sequence is + 4, + 6, + 8, + 10, ............

So, next term after 29 = 29 + 12 = 41.

The term after 41 will then be (41 + 14) i.e., 55.

∴ 41 is missing.

10. Find the missing term : 4, 6, 10, 16, 24, ?

a) 40

b) 34

c) 30

d) 28

Explanation: 1st term : 4

2nd term : 4 + 2 = 6

3rd term : 6 + 4 = 10

4th term : 10 + 6 = 16

5th term : 16 + 8 = 24

So,

6th term : 24 + 10 = 34