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What is the next number in the series 2, 1, 12,...

What is the next number in the series 2, 1, 12, 14...

A.

13

B.

28

C.

37

D.

18

Correct answer is D

2, 1, 12, 14.....

There are 4 terms in the series
Therefore the next number will be the 5th term

Tn = arn1 (formular for geometric series)

a = first term = 2

r = common rate = next termprevious term = 12

n = number of terms

T5 = 5th term = ?

T5 = ar51

= ar4

= 2 × (arn1)4

= 2 × 116

= 18