SSC CGL Number Series Questions & Solutions

A sample of real SSC CGL Number Series past-year questions, each with a worked solution and the correct answer highlighted. AthenaPrep has 921 Number Series questions in all — sign up free to practise them timed.

Q1.SSC 2024
In the following question, select the missing number from the given series.

2673, 891, 297, 99, ?, 11
- 43
- 33
- 23
- 10
Show solution
To find the missing number in the series 2673, 891, 297, 99, ?, 11, we observe the pattern of division by 3:
2673 ÷ 3 = 891
891 ÷ 3 = 297
297 ÷ 3 = 99
99 ÷ 3 = 33
33 ÷ 3 = 11
Thus, the missing number is 33 (Option B).

— worked solution by Athena AI
Q2.SSC 2023
Which of the following numbers will replace the question mark (?) in the given series?
239, 274, 309, 354, 399, 454, ?
- 499
- 474
- 539
- 509
Show solution
The differences between the numbers are:
274 - 239 = 35, 309 - 274 = 35, 354 - 309 = 45, 399 - 354 = 45, 454 - 399 = 55.
The next difference is 55 + 10 = 65.
So, 454 + 55 = 509.
Thus, the answer is D. 509.

— worked solution by Athena AI
Q3.SSC 2021
Which number will replace the question mark (?) in the following number series?
86, 74, 84, 76, ?, 78, 80
- 80
- 82
- 78
- 84
Show solution
To find the missing number in the series 86, 74, 84, 76, ?, 78, 80, we observe the pattern: the series alternates between subtracting and adding. Starting from 86, we subtract 12 to get 74, then add 10 to get 84, subtract 8 to get 76, and then add 6 to find the missing number. Thus, 76 + 6 = 82. The next number is 78, confirming the pattern. Hence, the answer is B. 82.

— worked solution by Athena AI
Q4.SSC 2020
Select the number that can replace the question mark (?) in the following series.
3, 12, 36, 80, ?, 248
- 149
- 146
- 147
- 152
Show solution
Given series 3, 12, 36, 80, ?, 248
take of difference 12-3 = 9, 36-12= 24, 80-36= 44 ,......
Again take difference of difference 24-9 = 15 , 44-24 = 20 next 25 and so on
then 44 + 25 = 69
therefore ? = 80+ 69 = 149 Ans
Q5.SSC 2019
Select the option that is related to the third number in the same way as the second number is related to the fast number.
15 : 25 :: 24 : .......
- 45
- 32
- 35
- 40
Show solution
The pattern followed is:
5 x 3 = 15
5 x 5 = 25
Now, 24/3 = 8
Hence, 8 x 5 = 40
Q6.SSC 2019
Select the option that will correctly replace the question mark (?) in the series.
15, 19, 35, 71, ?
- 125
- 141
- 145
- 135
Show solution
The series shows a pattern of doubling and adding:
15 to 19 (add 4),
19 to 35 (add 16),
35 to 71 (add 36).
The next addition should be 64 (doubling the previous addition), so 71 + 64 = 135.
Thus, the correct answer is D.

— worked solution by Athena AI
Q7.SSC 2019
Select the term that will come next in the following series.
3, 4, 5, 6, 9, 10, 11, 12, 15, ?
- 16
- 17
- 14
- 18
Show solution
3,4,5,6
NOW SKIP TWO NUMBERS 7 & 8 .
9, 10,11,12
NOW SKIP AGAIN TWO NUMBERS 13 & 14
15 , 16 ,17 ,18
SO THE NEXT IS 16.
Q8.SSC 2019
Select the number that can replace the question mark (?) in the following series.
101, 106, 116, 131, 151, ?
- 156
- 146
- 166
- 176
Show solution
Given series :
101, 106, 116, 131, 151, ?
The pattern followed here is :
The difference between the two consecutive terms is increasing by 5.
i.e;
106 - 101 = 5
116 - 106 = 10
131 - 116 = 15
151 - 116 = 20
Similarly,
151 + 25 = 176
Option D is correct.
Q9.SSC 2018
In the following question, select the missing number from the given alternatives.
18, 45, 112.5, ?, 703.125
- 217.5
- 262.25
- 281.25
- 273.75
Show solution
The series is 18, 45, 112.5, ?, 703.125. The pattern involves multiplying by 2.5:
18 * 2.5 = 45
45 * 2.5 = 112.5
112.5 * 2.5 = 281.25
281.25 * 2.5 = 703.125.
Therefore, the answer is C. 281.25.

— worked solution by Athena AI
Q10.SSC 2017
In the following question, select the missing number from the given series.

3, 8, 5, 27, 8, 64, 12, 125, 17, ?
- 216
- 361
- 625
- 441
Show solution
The given series is a combination of 2 series at alternate positions :
I : 3 , 5 , 8 , 12 , 17
II : 8 , 27 , 64 , 125
The missing number is from the second series which is the cube of natural numbers, next number = $6^3=216$
=> Ans - (A)
Q11.SSC 2016
A series is given, with one term missing. Choose the correct alternative from the given ones that will complete the series.

6, 10, 18, 34, ?, 130
- 78
- 52
- 66
- 94
Show solution
Numbers of the form $2^n$ are added.
6 $+2^2$ = 10
10 $+2^3$ = 18
18 $+2^4$ = 34
34 $+2^5$ = 66
66 $+2^6$ = 130
=> Ans - (C)
Passage
In each of the following questions, select the missing number from the given responses :
Q12.SSC 2013
- 176
- 166
- 116
- 66
Show solution
Number obtained by leaving the first two digits from right - the first two digits from right = Required value.
54-30 =28
112-42=70
x-28 =38
x=66
Hence Option D is the correct answer.

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SSC CGL Number Series previous year questions with solutions — AthenaPrep

SSC CGL Number Series Questions & Solutions

Q1.SSC 2024

In the following question, select the missing number from the given series.

2673, 891, 297, 99, ?, 11

Show solution

To find the missing number in the series 2673, 891, 297, 99, ?, 11, we observe the pattern of division by 3:

2673 ÷ 3 = 891

891 ÷ 3 = 297

297 ÷ 3 = 99

99 ÷ 3 = 33

33 ÷ 3 = 11

Thus, the missing number is 33 (Option B).

— worked solution by Athena AI

Q2.SSC 2023

Which of the following numbers will replace the question mark (?) in the given series?
239, 274, 309, 354, 399, 454, ?

Show solution

The differences between the numbers are:

274 - 239 = 35, 309 - 274 = 35, 354 - 309 = 45, 399 - 354 = 45, 454 - 399 = 55.

The next difference is 55 + 10 = 65.

So, 454 + 55 = 509.

Thus, the answer is D. 509.

— worked solution by Athena AI

Q3.SSC 2021

Which number will replace the question mark (?) in the following number series?
86, 74, 84, 76, ?, 78, 80

Show solution

To find the missing number in the series 86, 74, 84, 76, ?, 78, 80, we observe the pattern: the series alternates between subtracting and adding. Starting from 86, we subtract 12 to get 74, then add 10 to get 84, subtract 8 to get 76, and then add 6 to find the missing number. Thus, 76 + 6 = 82. The next number is 78, confirming the pattern. Hence, the answer is B. 82.

— worked solution by Athena AI

Q4.SSC 2020

Select the number that can replace the question mark (?) in the following series.
3, 12, 36, 80, ?, 248

Show solution

Given series 3, 12, 36, 80, ?, 248

take of difference 12-3 = 9, 36-12= 24, 80-36= 44 ,......

Again take difference of difference 24-9 = 15 , 44-24 = 20 next 25 and so on

then 44 + 25 = 69

therefore ? = 80+ 69 = 149 Ans

Q5.SSC 2019

Select the option that is related to the third number in the same way as the second number is related to the fast number.
15 : 25 :: 24 : .......

Show solution

The pattern followed is:

5 x 3 = 15

5 x 5 = 25

Now, 24/3 = 8

Hence, 8 x 5 = 40

Q6.SSC 2019

Select the option that will correctly replace the question mark (?) in the series.
15, 19, 35, 71, ?

Show solution

The series shows a pattern of doubling and adding:
15 to 19 (add 4),
19 to 35 (add 16),
35 to 71 (add 36).
The next addition should be 64 (doubling the previous addition), so 71 + 64 = 135.
Thus, the correct answer is D.

— worked solution by Athena AI

Q7.SSC 2019

Select the term that will come next in the following series.
3, 4, 5, 6, 9, 10, 11, 12, 15, ?

Show solution

3,4,5,6

NOW SKIP TWO NUMBERS 7 & 8 .

9, 10,11,12

NOW SKIP AGAIN TWO NUMBERS 13 & 14

15 , 16 ,17 ,18

SO THE NEXT IS 16.

Q8.SSC 2019

Select the number that can replace the question mark (?) in the following series.
101, 106, 116, 131, 151, ?

Show solution

Given series :

101, 106, 116, 131, 151, ?

The pattern followed here is :

The difference between the two consecutive terms is increasing by 5.

i.e;

106 - 101 = 5

116 - 106 = 10

131 - 116 = 15

151 - 116 = 20

Similarly,

151 + 25 = 176

Option D is correct.

Q9.SSC 2018

In the following question, select the missing number from the given alternatives.
18, 45, 112.5, ?, 703.125

217.5
262.25
281.25
273.75

Show solution

The series is 18, 45, 112.5, ?, 703.125. The pattern involves multiplying by 2.5:

18 * 2.5 = 45

45 * 2.5 = 112.5

112.5 * 2.5 = 281.25

281.25 * 2.5 = 703.125.

Therefore, the answer is C. 281.25.

— worked solution by Athena AI

Q10.SSC 2017

In the following question, select the missing number from the given series.

3, 8, 5, 27, 8, 64, 12, 125, 17, ?

Show solution

The given series is a combination of 2 series at alternate positions :

I : 3 , 5 , 8 , 12 , 17

II : 8 , 27 , 64 , 125

The missing number is from the second series which is the cube of natural numbers, next number = $6^3=216$

=> Ans - (A)

Q11.SSC 2016

A series is given, with one term missing. Choose the correct alternative from the given ones that will complete the series.

6, 10, 18, 34, ?, 130

Show solution

Numbers of the form $2^n$ are added.

6 $+2^2$ = 10

10 $+2^3$ = 18

18 $+2^4$ = 34

34 $+2^5$ = 66

66 $+2^6$ = 130

=> Ans - (C)

Passage

In each of the following questions, select the missing number from the given responses :

Q12.SSC 2013

Show solution

Number obtained by leaving the first two digits from right - the first two digits from right = Required value.
54-30 =28
112-42=70
x-28 =38
x=66
Hence Option D is the correct answer.

909+ more Number Series questions inside

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SSC CGL Number Series previous year questions with solutions — AthenaPrep