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Which number can replace the question mark (?) in the following series? 1, 3, 7, 13, 21, 31, ?
Question

Which number can replace the question mark (?) in the following series?
1, 3, 7, 13, 21, 31, ?

A.

40

B.

41

C.

42

D.

43

Correct option is D

1, 3, 7, 13, 21, 31, ?
+2, +4, +6, +8, +10, +12
? = 31 + 12 = 43

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