Which one of the following is NOT a prime number?
Question and options
Which one of the following is NOT a prime number?
- 31
- 61
- 71
- 91
Answer and explanation
Correct answer: D - 91
91 = 7 x 13, so it is not prime. 31, 61 and 71 are all prime.
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CUSAT CAT LLM
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