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Question

What should come in place of the question mark (?) in the given series?

24 12 12 18 36 ?

The correct answer is

90

Each term is the previous term multiplied by a factor that rises by 0.5 each time.

24 × 0.5 = 12, 12 × 1 = 12, 12 × 1.5 = 18, 18 × 2 = 36.

Next factor is 2.5: 36 × 2.5 = 90.

Hence, the answer is 90.

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