SOLUTION: Is 191 a prime number.How do i find out?

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Question 4871: Is 191 a prime number.How do i find out?
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
First find the sqrt+%28191%29+ and find that it is a number between 13 and 14, since 13%5E2+=+169 and 13%5E2+=+196.

Now you must divide 191 by each prime number up to and including 14, and show that 191 is NOT divisible by any of those numbers. Since 191 is NOT divisible by 2, 3, 5, 7, 11, or 13, this is a prime number.

R^2 at SCC