# Sam's coach is twice as old as Sam. When Sam started soccer 10 years ago, his coach was four times his age. How old is Sam now?

Apr 19, 2018

$15$ years ago now.

#### Explanation:

Let Sam's age be $x$. Let Sam's coach's age be $2 x$.

Therefore,

$4 \left(x - 10\right) = 2 x - 10$

since $4$ times the age of Sam $10$ years ago was the same as the coach's $10$ years ago.

So

$4 x - 40 = 2 x - 10$

$\implies 2 x = 30$

Therefore, Sam's age is $15$.