Question

Ten years ago, a mother was 3 times as old as her son. 5 years ago she was 5/2 times her son's age. What is her present age?

• A. 35 years
• B. 30 years
• C. 55 years
• D. 45 years

Answer 1

Answer:

C. 55 years

presnt age of both son and mother is S and M respectively

10 years ago

$3(S-10)=(M-10)$

$3S-30=M-10$

$3S-M=20$

$6S-2M=40$----------------------1

5 years ago

$\frac52(S-5)=(M-5)$

$5S-25=2M-10$

$5S-2M=15$-----------2

solving both 1 and 2(1-2)

$S=25$

Mother age

$=5\times25-2M=15$

$125-2M=15$
$125-15=2M$

$M=110/2=55$