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If x, x+2 and x+4 are prime numbers, then find the number of possible solutions for x.

A.	1	B.	2
C.	3	D.	4

Answer and Explanation

Answer:1

Explanation:
For x=2, the numbers are: 2, 4, 6 … (only first number is a prime number)
For x=3, the numbers are: 3, 5, 7 … (all numbers are prime numbers)
For x=5, the numbers are 5, 7, 9 … (first two numbers are prime numbers)
Hence for all other possibilities of x as a prime number, x, x+2 and x+4 all are not prime numbers.
Therefore there is only one possibility of x.

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