Will is 4 years older than Mike. Together, the sum of their ages equals three times Mike's age. How old is each person?
Mike is 4 and because Will is 4 years older Will is 8.
Let's call Mike's age
Therefore, because Will is 4 years older than Mike his age can be described as
And "three times Mike's age" can therefore be written as
The sum of Mike's and Will's age can be written as
And this is equal to