Explain why 7 × 11 × 13 + 13 and 7 × 6 × 5 × 4 × 3 × 2 × 1 + 5 are composite numbers?

Composite numbers can be defined as natural numbers that have more than two factors. In other words, a number that is divisible by a number other than 1 and the number itself, is called a composite number.

Answer: The given numbers have more than 2 factors. Therefore, they are composite numbers.

Let's look into the solution.

Explanation:

7× 11 × 13 + 13 can be wriiten as 13 (7× 11 + 1).

Clearly, this has more than 2 factors.

So, 7× 11 × 13 + 13 is a composite number.

7 × 6 × 5 × 4 × 3 × 2 × 1 + 5 can be wriiten as 5 (7 × 6 × 4 × 3 × 2 × 1 + 1). 

Clearly, this has more than 2 factors.

So, 7 × 6 × 5 × 4 × 3 × 2 × 1 + 5 is a composite number.

Thus, the given numbers have more than 2 factors. Therefore, they are composite numbers.