If X ∈ N and 17 < x < 23, and x is a prime number, then which of the following represents the list form of the set of such numbers?

Question: If X ∈ N and 17 < x < 23, and x is a prime number, then which of the following represents the list form of the set of such numbers?

Solution:
দেয়া আছে:
X ∈ N and 17 < x < 23

List all natural numbers between 17 and 23
⇒ 18, 19, 20, 21, 22

∴ Identify the prime numbers among them
⇒ 18 → divisible by 2; not prime.
⇒ 19 → prime.
⇒ 20 → divisible by 2; not prime.
⇒ 21 → divisible by 3 and 7; not prime.
⇒ 22 → divisible by 2; not prime.

∴ List of prime numbers in this range
{19}.