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Which of the following numbers will replace the question mark (?) in the given series?78, 32, 68, 64, 58, 128, 48, 256, ?
Question

Which of the following numbers will replace the question mark (?) in the given series?
78, 32, 68, 64, 58, 128, 48, 256, ?

A.

28

B.

24

C.

34

D.

38

Correct option is D

Given: 78, 32, 68, 64, 58, 128, 48, 256, ?
Logic: Series follow the pattern alternating between two sequences:
Sequence 1: 78, 68, 58, 48, ? (decreasing by 10)
Sequence 2: 32, 64, 128, 256 (doubling each time)
78-10=68
32×2=64
68-10=58
64×2=128
58-10=48
128×2=256
Similarly,
48-10=38
Thus, Option D is the correct answer.

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