5, 15, X, 51, 53, 159, 161. Find X.
Question and options
5, 15, X, 51, 53, 159, 161. Find X.
- 16
- 17
- 30
- 34
Answer and explanation
Correct answer: B - 17
The pattern alternates x3 and +2: 5x3=15, 15+2=17, 17x3=51, 51+2=53, 53x3=159, 159+2=161. X=17.
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CUSAT CAT Five-Year LL.B.
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