Question

Explain why $11\times 13\times 15\times 17÷17$ is a composite number.

Answer 1

Given number is $11\times 13\times 15\times 17÷17$

On simplifying the number, we get:

$11\times 13\times 15$

We know that, $prime\times composite=composite$

Here, out of $11,13\text{and}15,15$ is a composite number.

So, the overall product will also be composite.

Hence, the given number is composite because it contains a composite number, $15$.