Question

Which of the following is a composite number?

A. 61
B. 63
C. 13
D. 31

Is it B? I don't know

Answer 1

A composite number is the opposite of a prime number, if you know what that is.

A prime number is a number that can only be gotten by multiplying itself and 1.
A composite number is a number that has more than 2 factors.

So that means that it is B, because you can multiply 7 and 9 for example to get it.

Answer 2

B because 7 and 9 can go into it since they are factors of 63. The rest of the numbers don’t have any prime number except for one and itself