Question

Which of the following numbers are prime:

• A. $23$
• B. $51$
• C. $37$
• D. $26$

Answer 1

Answer: (A), (C)

$37$

Step 1: Explanation for correct option:

Option A.$23$

The prime number is a natural number that has only two factors that is $1$ and the number itself.

Prime factorization of $23$:

$23=1\times 23$

Here $23$ have only two factors. So, they are prime numbers.

And hence Option A is the correct option.

Option C. $37$

Prime factorization of $37$:

$37=1\times 37$

Here $37$ have only two factors. So, they are prime numbers.

And hence Option C is the correct option.

Step 2: Explanation for incorrect option:

Option B. $51$

Prime factorization of $51$:

$51=1\times 3\times 17$

Here $51$ have factors more than two. So, it is not prime numbers.

And hence Option B is incorrect option

Option D. $26$

Prime factorization of $26$:

$26=1\times 2\times 13$

Here $26$ have factors more than two. So, it is not prime numbers.

And hence Option D is incorrect option

Hence the correct options are Option A and Option C.