SOLUTION: four years ago, a man's age was three years more than thrice his son's age. fifteen years hence, his age will be five years less than twice his son's age . find the man's present a
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-> SOLUTION: four years ago, a man's age was three years more than thrice his son's age. fifteen years hence, his age will be five years less than twice his son's age . find the man's present a
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Question 608482: four years ago, a man's age was three years more than thrice his son's age. fifteen years hence, his age will be five years less than twice his son's age . find the man's present age. Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! four years ago, a man's age was three years more than thrice his son's age. fifteen years hence, his age will be five years less than twice his son's age . find the man's present age.
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Equations:
m-4 = 3(s-4)+3
m+15 = 2(s+15)-5
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Rearrange:
m - 7 = 3s - 12
m +20 = 2s + 30
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Modify:
m - 3s = -5
m - 2s = 10
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Subtract and solve for "m":
son's age = 15
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Solve for "m":
m - 2s = 10
m -2*15 = 10
man's age = 40
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Cheers,
Stan H.
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