Question

Father's age is $10$ more than twice age of his son. What is the age of son if fathers age is $40$?

• A. $10$
• B. $12$
• C. $15$
• D. $18$

Answer 1

The correct option is C $15$

Let father's age is $F$ and son's age be $S$
$F=2S+10$
The equation is in two variable.
$F=40$
$S=\frac{F-10}{2}=\frac{40-10}{2}=15$