Peter was asked how old he was - Math Riddle

96.Math Riddles

Peter was asked how old he was. His reply was like this; In a period of 2 years my age will be twice my age when you asked this five years ago. How old is he?

A.10
B.9
C.14
D.12

Explanation :  

Let Peter's age be X Years
X+2=2(X 5)
X+2=2X 10
X=12