Question

Is 25 a composite number?

Answer 1

Yes

Explanation:

25 has more factors than just 1 and 25 making it composite.

The list of factors that it has is 1, 5, and 25.

Answer 2

A composite number is a product of prime numbers.
So to answer your question. Yes as it is a product of two primes.
That is the prime 5`-> 5xx5=25`

Explanation:

A prime number is a number that can only be divided by 1 and itself and no other whole number to give a whole number answer.

Any number that is a product of primes is a composite number.

Consider the prime factor tree:

3 and 79 are primes in that they can only be divided by themselves and 1 to give whole number answers.

But `3xx79=237` so 237 is composite

Hear is another composite split into its prime factors

So the composite 638 is a product of the prime {2,11,29}

In that `2xx11xx29=638`

I quick search on the internet will lists of prime numbers. If you can it is a good idea to try and remember some of them. In England schools encourage the remembering the primes numbers up 97