SOLUTION: Mike's son John is exactly one fifth of Mike's age. In 21years time, Mike will be exactly twice John's age. How old is John now?
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Question 1039637: Mike's son John is exactly one fifth of Mike's age. In 21years time, Mike will be exactly twice John's age. How old is John now?
Answer by addingup(3677) (Show Source): You can put this solution on YOUR website!
J = 1/5M
M+21 = 2(J+21)
M+21 = 2(1/5M+21)
M+21 = 2/5M+42
M = 2/5M + 21
M-2/5M = 21
3/5M = 21
M = 21(5/3) = 105/3 = 35 Mike is 35 years old and John is 1/5(35) = 7 years old.
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