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Which of the following numbers will replace the question mark (?) in the given series?13, 29, 61, 125, 253, 509, ?​​
Question

Which of the following numbers will replace the question mark (?) in the given series?
13, 29, 61, 125, 253, 509, ?​​

A.

1099

B.

1029

C.

1021

D.

1089

Correct option is C

Given: 13, 29, 61, 125, 253, 509, ?​​
Logic: Each term = (Previous term × 2) + 3
13 × 2 + 3 = 29
29 × 2 + 3 = 61
61 × 2 + 3 = 125
125 × 2 + 3 = 253
253 × 2 + 3 = 509
Similarly;
509 × 2 + 3 = 1021
Thus, correct option is (c).

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