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?

1 Answer

Answer:

#15# years ago now.

Explanation:

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

Therefore,

#4(x-10) = 2x-10#

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

So

#4x - 40 = 2x - 10#

#=> 2x = 30#

Therefore, Sam's age is #15#.