IBPS RRBs Officer Scale I and II 13 Sep 2015 Paper

(5) Y’s present age = y years (let)
⇒ X’s present age = (3y + 3) years
⇒ Z’s present age = 2y years
According to the question,
3y + 3 – 2y = 12
y + 3 = 12
⇒ y = 12 – 3 = 9 years
⇒ Z’s present age = 2y
= 2 × 9
= 18 years