You can put this solution on YOUR website! Cheryl is three years more than three times as old as Ben. In 20 years the sum of their ages will be 87. How old is Ben now?
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let x= Ben's age
3x+3=Cheryl's age
..
In 20 years:
x+20=Ben's age
3x+3+20=3x+23=Cheryl'age
..
x+20+3x+23=87
4x=87-43
4x=44
x=11
How old is Ben now? 11