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125 114 175 291 tell which numbers are prime and composite

math question. help!

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prime numbers are numbers that can be divide by themselves and 1. composites are numbers that can be divided by other numbers. So whatever is not a prime number, is a composite number. Try and see which one it is by using a calculator and dividing it by small numbers (1,2,3,5,7,11, etc.). There are a few tricks. If it ends in an even number (0, 2, 4, 6, or 8) then it is NOT a prime number. Same goes with numbers ending with a 5 or 0 (they are always divisible by a 5). Here's a neat one: And if all the digits add up to a number divisible by 3, then it is also not a prime number. Ex: 291= 2+9+1=12.12 is divisible by 3, therefore the number 291 is NOT a prime number (it is divisible by 3 and 97). So, you tell me, which one of those numbers are prime?

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The third one
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Do you know what they mean?

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Ya. I figures out the first 2 and the last one but I'm struggling on the third 1
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175 is composite I belive
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Don't use ask.com to help with homework! It will hurt in the long run! Instead ask what prime and composite are and figure it out by yourself.

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I know what it is but I'm really struggling with the third 1
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If a number ends in 0 or 5 it is divisible by 5.
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291 is the prime

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Thx
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291/3 = 97
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They are all composite.

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A number is divisible by:
2 if it is even.
3 if the sum of its digits is divis. by 3
4 if the last 2 digits are divis. by 4
5 if it ends in 0 or 5
6 if it is even and divisible by 3
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Thx so much
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