# Easy Number System Solved QuestionAptitude Discussion

 Q. Two prime numbers $A, B(A < B)$ are called twin primes if they differ by 2 (e.g. 11,13,or 41,43....). If A and B are twin primes with $B > 23$, then which of the following numbers would always divide $A+B$?
 ✔ A. 12 ✖ B. 8 ✖ C. 24 ✖ D. None of these

Solution:
Option(A) is correct

Any prime number greater than 3 will be in the form of $6x+1$ or $6x-1$.

Thus, both prime number are twins:

Let first be $6x-1$
and 2nd be $6x+1$
$\text{Sum} = 12x$

Thus it is always divisible by 12.

## (1) Comment(s)

Krish
()

prime numbers near to 23 are 29 and 31 and both differ by 2

so,29+31=60 which is divisible by 12