Question 1046041: Five years ago, a grandmother was 4 times as old as her grandson was. Three years from now, she will only be 3 times as old as her grandson will be then. How old is the grandson now?
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! let g = grandmother's age now
lets = grandson's age
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Write an equation for each statement,simplify as much as possible
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Five years ago, a grandmother was 4 times as old as her grandson was.
g-5 = 4(s-5)
g- 5 = 4s - 20
g = 4s - 20 + 5
g = 4s - 15
Three years from now, she will only be 3 times as old as her grandson will be then.
g + 3 = 3(s+3)
g + 3 = 3s + 9
g = 3s + 9 - 3
g = 3s + 6
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How old is the grandson now?
g = g, therefore
4s - 15 = 3s + 6
4s - 3s = 15 + 6
s = 21 is the grandson's present age
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You can check this for yourself, find grandma's age and check it in one of the two statement.
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