Question 308775: Tim is 3 times older than Tina, 3 years ago the difference between their ages was 10 years, how old are they?
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! A silly problem but will follow it to the bitter end
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let a = Tim's age
let b = Tina's age
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Write an equation for each statement:
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"Tim is 3 times older than Tina,"
a = 3b
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" 3 years ago the difference between their ages was 10 years,"
The difference between their ages will always be 10 yrs
Prove it with the equation
(a-3) - (b-3) = 10
Remove brackets
a - 3 - b + 3 = 10
a - b = 10; same no matter what year it is
a = (b+10)
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how old are they?
Replace a with 3b
3b = b+10
3b - b = 10
2b = 10
b = 5 yrs old, a = 15 yrs old
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