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

Sol. We have, 7 x 11 x 13 + 13 = 1001 + 13 = 1014
1014 =2 x 3 x 13 × 13

So, it is the product of more than two prime numbers. 2, 3 and 13.

Hence, it is a composite number. 7 x 6x 5x 4 x 3 x 2 x 1 x 3 x 2 x 1 + 5 = 5040+5=5045
5045 = 5 x 1009

It is the product of prime factors 5 and 1009.

Hence, it is a composite number.

Ithink you're supposed to multiply 12.50 which is how much he makes per hour and then multiply it by each number then add whats left togrther and there's your answer