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#1 2008-11-20 06:48:44
- Lou
- Guest
age
Paige is 10 years older than her brother. In 7 years, Paige will be twice as old as her brother. How old are Paige and her brother now?
#2 2008-11-20 07:10:45
- mathsyperson
- Moderator
- Registered: 2005-06-22
- Posts: 4,900
Re: age
Let's say that Paige is "P" years old. She's 10 years older than her brother, so he must be P-10 years old.
In 7 years, Paige will be P+7 and her brother will be (P-10)+7 = P-3.
She will be twice his age then, and so P+7 = 2(P-3).
Solving this equation gives:
P+7 = 2P-6
7 = P-6
13=P
P=13.
So Paige is 13 years old and her brother is 3.
(In seven years, she will be 20 years old and her brother will be 10)
Why did the vector cross the road?
It wanted to be normal.
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