Answer :
133 can be divided by 7, so it is not prime.
143 can be divided by 11, so it is not prime.
153 can be divided by 3, so it is not prime.
163 can only be divided by 1 and itself, so it is prime.
143 can be divided by 11, so it is not prime.
153 can be divided by 3, so it is not prime.
163 can only be divided by 1 and itself, so it is prime.
163 is a prime number because it has no multiples other then one and itself