Number Series Questions and Answers Part-19

1. Find the missing term: 36, 34, 30, 28, 24, ?
a) 20
b) 23
c) 22
d) 26

Answer: c
Explanation: Missing term is 22.

2. Find the missing term : 3, 5, 9, 17, ?
a) 33
b) 42
c) 26
d) 65

Answer: a
Explanation: 1st term : 3
2nd term : 3 + 2 = 5
3rd term : 5 + 4 = 9
4th term : 9 + 8 = 17
So,
5th term : 17 + 16 = 33

3. Find the missing term :9*2 : 9*9 : : 9*5 : ?
a) 9*4
b) 9*6
c) 9*7
d) 9*8

Answer: b
Explanation: 9 × 2 : 9 × 9 : : 9 × 5 : ?
18 : 81 : : 45 : 9 × 6
So. 9 × 6 will come in place of question mark.

4. Find the missing term : 1, 0, 3, 2, 5, 6, ?, 12, 9, 20
a) 9
b) 10
c) 7
d) 8

Answer: c
Explanation: There are two series in the given question.
1st series: 1, 3, 5, 7, 9 ... ( each next term are generated by adding 2)
2nd series: 0, 2, 6, 12, 20 ... ( each next term are generated by adding 2n [where n=1,2,3,4...])

5. Find the missing term : 5, 16, 51, 158, ?
a) 1452
b) 483
c) 481
d) 1454

Answer: c
Explanation: The series is as follows:
5 × 3 + 1 = 16
16 × 3 + 3 = 51
51 × 3 + 5 = 158
158 × 3 + 7= 481

6. Find out the wrong term: 1, 5, 9, 15, 25, 37, 49
a) 9
b) 15
c) 25
d) 37

Answer: b
Explanation: The terms of the given series are 12 , (22 + 1), 32 , (42 + 1), 52 , (62 + 1), 72
So, 15 is wrong and must be replaced by (42 + 1) i.e., 17.

7. Find out the wrong term: 445, 221, 109, 46, 25, 11, 4
a) 25
b) 46
c) 109
d) 221

Answer: b
Explanation: 3 is subtracted from each number and the result divided by 2 to obtain the next number of the series,
So, 46 is wrong and must be replaced by (109 - 3)/2 i.e., 53.

8. Find out the wrong term: 11, 5, 20, 12, 40, 26, 74, 54
a) 5
b) 20
c) 40
d) 26

Answer: c
Explanation: The given sequence is a combination of two series:
I: 11, 20, 40, 74 and
II: 5, 12, 26, 54
The correct pattern in I: is + 9, + 18, + 36,.....
So, 40 is wrong and must be replaced by (20 + 18) i.e., 38.

9. Find out the wrong term: 93, 309, 434, 498, 521, 533
a) 309
b) 434
c) 498
d) 521

Answer: d
Explanation: The correct pattern is + 63 , + 53 , + 43 , + 33 , ............
So, 521 is wrong and must be replaced by (498 + 33 ) i.e., 525.

10. Find out the wrong term: 1, 5, 5, 9, 7, 11, 11, 15, 12, 17
a) 11
b) 12
c) 17
d) 15

Answer: b
Explanation: The given sequence is a combination of two series :
I: 1, 5, 7, 11, 12 and
II: 5, 9, 11, 15, 17
The pattern in both I and II is + 4, + 2, + 4, + 2,

So, 12 is wrong and must be replaced by (11 + 2) i.e., 13.