SOLUTION: fred is 3 times older than his sister Mary, four years ago he was 5 times as old as his sister. find their present ages

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Question 989454: fred is 3 times older than his sister Mary, four years ago he was 5 times as old as his sister. find their present ages
Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
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M=Mary's age; F=Fred's age=3M
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F-4=5(M-4)
3M-4=5M-20
16=2M
M=8 ANSWER 1: Mary is 8 years old.
F=3M=3(8)=24 ANSWER 2: Fred is 24 years old.
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CHECK:
F-4=5(M-4)
24-4=5(8-4)
20=3(4)
20=20