Question

[3,5] [5,7] [7,9] [11,13] Which among the following are not twin prime numbers.

Answer 1

Answer:

(7,9) are not twin primes because 9 is not a prime number.

Answer 2

Answer:

⇒ (7,9) are not twin prime

Step-by-step explanation:

Definition- Two prime numbers which differ by 2 is known as twin primes. Among the given pairs,

1. (3,5) - Both 3 and 5 are prime numbers and they differ by 2. Hence they are twin prime.

2. (5,7) - Both 5 and 7 are prime numbers and they differ by 2. Hence they are twin prime.

3. (7,9) - This pair contains a composite number i.e 9. Hence they are not twin prime.

4. (11, 13) - Both 11 and 13 are prime numbers and they differ by 2. Hence they are twin prime.