SOLUTION: wich number is a prime number 1 12 31 99

Question 61876: wich number is a prime number
1
12
31
99
Answer by funmath(2933) (Show Source): You can put this solution on YOUR website!
wich number is a prime number
1
12

99
:
1 is unusual because it seams like it should be prime, but the math gods decided it wasn't/
12=2*6, 3*4 so it's a composite number.
99=9*11,3*33 so it's a composite number as well
The only factors of 31 is 1*31 so it's prime.
Happy Calculating!!!
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