DS Question - 4

Is the integer x divisible by 3?

1) The last digit in x is 3.
2) x+5 is divisible by 6.

Answer - B

Statement (1) is not sufficient.
If x is 33, then x is divisible by 3, and (1) holds, but if x=43, then (1) is true but x is not divisible by 3.

Statement (2) is sufficient. According to it , there exists an integer k such that x+5 = 6k => x = 6k-5 => x/3 = (6k-5)/3 = x/3 = (2k) - 5/3 => x is not divisible by 3.

Hence B is the answer i.e the (2) statement alone is sufficient to answer the question but (1) statement alone is not sufficient to answer the question.