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Which of the following numbers will replace the question mark (?) in the given series? 65, 90, 107, 116, 121, ?
Question

Which of the following numbers will replace the question mark (?) in the given series?
65, 90, 107, 116, 121, ?

A.

123

B.

125

C.

122

D.

124

Correct option is C

Given:
65, 90, 107, 116, 121, ?
Logic: +(52+0), + (42+1), +(32+0), +(22+1), +(12+0),.....
90 - 65 = +(52+0) = 25
107 - 90 = (42+1) = 17
116 - 107 = +(32+0) = 9
121 - 116 = +(22+1) = 5 
? - 121 = +(12+0) = 1 
? = 121 + 1 
? = 122
So the next number is : 121+1 = 122
Thus the correct answer is (C)

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