Discussion

The sum of ages of A and B is 60 years. If A is twice as old as B, what is B's age ?

Answer: C

B's age is 20 years.

A is twice as old as B, so A = 2B, and together they total 60:

\[ \begin{aligned} 2B + B &= 60 \\ 3B &= 60 \\ B &= 20 \end{aligned} \]

So B is 20 and A is 40. Check: 40 + 20 = 60, and 40 is twice 20.

With B at 15, A would be 30 and the total only 45; with 18 the total is 54, and with 25 it is 75. Only 20 gives 60.

No comment is present. Be the first to comment.

Loading…