Question 214369
let d = david's age now.
let a = aaron's age now.
let e = ellen's age now.
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In ten years ,david will be four times as old as aaron.
d+10 = 4*(a+10) = 4a+40
d = 4a+30
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Twenty years ago,david was twice as old as ellen.
d-20 = 2*(e-20)
d-20 = 2e-40
d = 2e-20
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If david is seven years older than ellen,how old is aaron?
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d = e+7
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Since d = 2e-20 and d = e+7, then 2e-20 must equal e+7
Equation to solve is:
2e-20 = e+7
This results in e = 27
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Ellen's age is 27
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Since d = e+7, this means that David is 7 years older than Ellen which makes David = 34 years old.
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Since d = 4a+30, and d = 34, then we have:
34 = 4a+30
This results in a = 1
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David is 34 years old
Aaron is 1 year old
Ellen is 27 years old.
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In 10 years Aaron is 11 and Dave is 44.
4 * 11 = 44 so this part of the original equation is good.
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20 years ago, David was twice as old as Ellen.
34-20 = 14
27-20 = 7
14/7 = 2 so this part of the equation is good also.
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Answer to your question is:
Aaron is 1 year old.
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