Problem Solving

teejaycrown wrote:Whats the tens digit of the positive integer r?

1. The tens digit of r/10 is 3
2. The hundreds digits of 10r is 6

Let us assume that r = xyz, where tens digit = y.
We have to find the value of y.

(1) The tens digit of r/10 is 3.
r/10 = xy.z, which implies that tens digit is x. So, x = 3, but we cannot find y from here; NOT Sufficient.

(2) The hundreds digits of 10r is 6.
10r = xyz0, which implies hundreds digit is y here.
So, y = 6; SUFFICIENT.

The correct answer is B.