# Number Series – Questions & Answers

Number Series Questions and Answers is about the Missing numbers in a series that you can expect for Competitive Examinations. Here you can find out practice problems from the topic Missing Number Series.

Number Series – Logical Reasoning Questions and Answers
Missing Number Series for Competitive Exams

1. Find the missing number: 32, 48, 72, 108, ——
Explanation: 32 x 3/2 = 48
48 x 3/2 = 72
72 x 3/2 = 108
108 x 3/2 = 162
2. Find the missing number: 0.5, 1.5, 4.5, 13.5, ——-
Explanation: 0.5 x 3 = 1.5
1.5 x 3 = 4.5
4.5 x 3 = 13.5
13.5 x 3 = 40.5
3. Find the missing number: 3, 9, 27, 81, ——–
Explanation: 3 x 3 = 9, 9 x 3 = 27, 27 x 3 = 81, 81 x 3 = 243
4. Find the missing number: 4, 9, 13, 22, 35, ——
Explanation: 4 + 9 = 13, 13 + 9 = 22, 22 + 13 = 35, 35 + 22 = 57
5. Find the missing number: 4, 25, 64, ——
Explanation: Square of the numbers 2, 5, 8, 11 ———–
6. Find the missing number: 199, 195, 186, 170, ——-
Explanation: 199 – 195 = 4, 195 – 186 = 9, 186 – 170 = 16, 170 – 25 = 145
7. Find the missing number: 3, 12, 24, 96, 192, ——
Explanation: 3 x 4 = 12, 12 x 2 = 24, 24 x 4 = 96, 96 x 2 = 192, 192 x 4 = 768
Multiplication with 4, 2, 4, 2, 4 ———————–
8. Find the missing number: 2, 7, 3, 26, 4, ——-
Explanation: Consider two series 2, 3, 4, ———— and 7, 26, ———
Find cube of 2, 3, 4 ———- and subtract 1 from each.
i.e. Cube of 2 = 8, 8 – 1 = 7.
Cube of 3 = 27, 27 -1 = 26
Cube of 4 = 64, 64 – 1 = 63
9. Find the missing number: 1, 3, 7, 15, ————
Explanation: 1 + 2 = 3, 3 + 4 = 7, 7 + 8 = 15, 15 + 16 = 31
10. Find the missing number: 5, 9, 4, 8, 3, 7, ———
Explanation: Consider two series 5, 4, 3, ———- and 9, 8, 7, ————-
Subtract 1 from each number, we get 5 – 1 = 4, 4 – 1 = 3, 3 – 1 = 2
11. Find the missing number: 2, 5, 9, 19, 37, ———
Explanation: 2 x 2 + 1= 5
5 x 2 – 1 = 10 – 1 = 9
9 x 2 + 1 = 18 + 1 = 19
19 x 2 – 1 = 38 – 1 = 37
37 x 2 + 1 = 74 + 1 = 75
12. Find the missing number: 7, 12, 19, ————-
Explanation: 7 + 5 = 12, 12 + 7 = 19, 19 + 9 = 28
Increased by 5, 7, 9, ————-
13. Find the missing number: 3, 12, 30, 66, ———–