Which number is composite?

a. 51

b. 17

c. 29

d. 41

51

Step-by-step explanation:

A composite number is one in which the number is made up of 2 or more primes. The primes can be the same.

A prime number is divisible only by itself and 1. So here are some composites

Composites

20: 2 * 2 * 5 [no even number is a prime number except 2].

45:3 * 3 * 5

9: 3 * 3 The primes can be the same.

51: 3 * 17

Primes

2 3 5 7 11 13 17 19 ... and more to follow.

41 can only be divided by itself and 1. It is a prime.

29 can only be divided by itself and 1. It is a prime.