SOLUTION: Please help me form the equation for this question Greg is 3 times David's age, how old are Greg and David now if in 10 years time the sum of their ages will be 72 Thankyou Croml

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Please help me form the equation for this question Greg is 3 times David's age, how old are Greg and David now if in 10 years time the sum of their ages will be 72 Thankyou Croml      Log On


   

Question 788945: Please help me form the equation for this question
Greg is 3 times David's age, how old are Greg and David now if in 10 years time the sum of their ages will be 72
Thankyou Cromlix for your help
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Greg is 3 times David's age, how old are Greg and David now if in 10 years time the sum of their ages will be 72
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Equations:
g = 3d
g+10 + d+10 = 72
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Substitute for "g" and solve for "d":
3d+10 + d+10 = 72
4d + 20 = 72
4d = 52
d = 13 (David's age now)
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g = 3d
g = 39 (Greg's age now)
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Cheers,
Stan H.
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