SOLUTION: John's and Mary's ages sum up to 25.Eight years ago,John was twice as old as Mary.How old are they now?

Question 1021451: John's and Mary's ages sum up to 25.Eight years ago,John was twice as old as Mary.How old are they now?
Answer by macston(5194) (Show Source): You can put this solution on YOUR website!
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J=John's age; M=Mary's age
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J+M=25
J=25-M
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J-8=2(M-8)
(25-M)-8=2M-16
17-M=2M-16
33-M=2M
33=3M
11=M
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Mary is 11 years old.
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J=25-M=25-11=14
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John is 14 years old.
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ANSWER: John is 14 years old and Mary is 11 years old
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CHECK:
J-8=14-8=6
8 years ago, John was 6 years old.
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M-8=11-8=3
8 years ago, Mary was 2 years old.
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8 years ago, John was twice as old as Mary:
6yrs=2(3yrs)
6yrs=6yrs
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