# Is 1 a common factor?On the tv show "Are You Smarter Than A Fifth Grader" this guy had a question that was how many common factors do 28 and 32 have. He answered 2 and said the common factors were...

Is 1 a common factor?

On the tv show "Are You Smarter Than A Fifth Grader" this guy had a question that was how many common factors do 28 and 32 have. He answered 2 and said the common factors were 2 and 4 and i thought he was right, but the answer was 1,2, and 4. Is this right or were they wrong.........?????????

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### 3 Answers

Yes, One is a common factor. We usually don't count it when we are factoring since it doesnt change the problem but it is still a common factor. We usually count it when we are trying to find roots.

I personally feel like the guy got fooled because he was right, and he wouldnt be the only one to leave out 1 as we usually don't metiong it.

The producers were right. 28 has factors of 1,2,4,7,14 and 28 while 32 has faxtors of 1,2,4,8,16,32.

As you can see. 32 and 28 have similar factors of 1,2 and 4. 1 is considered a factor as all numbers under the sun have a factor of 1, or you could say a common divisor tool.

Yes, it is a very good answer!

You know, 1 is the neutral element in multiplying, meaning that any number muliplied with 1, will remain unchanged.

From here, it will appear the conclusion that 1 is common divisor for any number, even for prime numbers.