Which of the following numbers will replace the question marks (?) in the given series?
1, 3, 6, 10, ?, ?, 28, 36, 45, 55
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 15, 21.
Given series: 1, 3, 6, 10, ?, ?, 28, 36, 45, 55
The series follows this pattern:
1 + 2 = 3
3 + 3 = 6
6 + 4 = 10
10 + 5 = 15
15 + 6 = 21
21 + 7 = 28
28 + 8 = 36
36 + 9 = 45
45 + 10 = 55
So, the missing terms in the series are 15, 21.