SOLUTION: mike's age is three-fourths of mary's age. in 5 years mike's age will be 7/9 mary's age . how old is mike now

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Question 304337: mike's age is three-fourths of mary's age. in 5 years mike's age will be 7/9 mary's age . how old is mike now
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
Mike=3x/4
Mary=x
(3x/4+5)=7/9(x+5)
3x/4+5=7(x+5)/9
3x/4+5=(7x+35)/9
(3x+5*4)/4=(7x+35)/9
(3x+20)/4=(7x+35)/9 cross multiply.
9(3x+20)=4(7x+35)
27x++180=28x+140
27x-28x=140-180
-x=-40
x=40 ans. for Mary's age now.
3*40/4=120/4=30 ans. for Mike's age now.
Proof:
30+5=7/9(40+5)
35=7/9*45
35=7*5
35=35