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In this question, a number series is given with one term missing. Choose the correct option that will continue the same pattern.

17, 19, 15, 23, 7, 39, ?

Solution

✅ Correct Option: 2

Let's look at consecutive differences:

17,19,15,23,7,39,?17, 19, 15, 23, 7, 39, ?

+2,−4,+8,−16,+32+2, -4, +8, -16, +32

The pattern:

Each difference alternates between ++ and −-

The absolute value doubles each time: 2,4,8,16,322, 4, 8, 16, 32

Therefore:

Next number should subtract 6464 from 3939

39−64=−2539 - 64 = -25

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