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Which of the following numbers will replace the question mark (?) in the given series? 28, 32, 39, 52, 74, ?
Question

Which of the following numbers will replace the question mark (?) in the given series?
28, 32, 39, 52, 74, ?

A.

108

B.

112

C.

100

D.

110

Correct option is A

Given:
28, 32, 39, 52, 74, ?
Logic: Double differences are increasing by +3 .
First differences:
32−28=4, 39−32=7, 52−39=13,  74−52=22
First differences: 4, 7, 13, 22
Double differences:
7−4=3, 13−7=6, 22−13=9
next difference will be:
? - 22= +12
? = 34
So, next number =74 + 34 = 108
Thus the correct option is (A)

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