SOLUTION: Together, Grandma and Grandpa are 140 years old. How old is Grandma if Grandpa was twice as old as Grandma was when Grandpa was as old as Grandma is now.
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Question 862659: Together, Grandma and Grandpa are 140 years old. How old is Grandma if Grandpa was twice as old as Grandma was when Grandpa was as old as Grandma is now. Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Together, Grandma and Grandpa are 140 years old.
How old is Grandma if Grandpa was twice as old as Grandma was when Grandpa was as old as Grandma is now.
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Let m = grandma's age
let p = grandpa's age
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Let d = the difference in their age d-m
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"Together, Grandma and Grandpa are 140 years old."
p + m = 140
" How old is Grandma if Grandpa was twice as old as Grandma was when Grandpa was as old as Grandma is now.
Write grandma's age as p-d
p - d = 2(p-d-d)
p - d = 2(p-2d)
p - d = 2p - 4d
4d - d = 2p - p
3d = p
Replace d with (p-m)
3(p-m) = p
3p - 3m = p
3p - p = 3m
3p = 3m
p = m
p = 1.5m
Replace p with 1.5m in the first equation
1.5m + m = 140
2.5m = 140
m = 140/2.5
m = 56 yrs is Grandma's age
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Check this find Grandpa's age: 1.5(56) = 84 hrs old, 28 yrs apart
"Grandpa was twice as old as Grandma was when Grandpa was as old as Grandma is now."
84 - 28 = 2(56 - 28)
56 = 2(28)
