Ten years ago a man was as old as his wife is now.

Simple patterns, variables, the order of operations, simplification, evaluation, linear equations and graphs, etc.
zackattack
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Ten years ago a man was as old as his wife is now.

Postby zackattack » Fri Apr 03, 2009 11:17 pm

Ten years ago a man was as old as his wife is now. The man is now twice as old as his wife was then. How old are they both now?

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stapel_eliz
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Postby stapel_eliz » Sat Apr 04, 2009 12:42 am

zackattack wrote:Ten years ago a man was as old as his wife is now. The man is now twice as old as his wife was then. How old are they both now?

Start naming things, and use the relationships between the people and the times to set up this "age" word problem:

. . .ages now:
. . . . .him: h
. . . . .wife: w

. . .ages 10 years ago:
. . . . .him: h - 10
. . . . .wife: w - 10

. . .relationships:
. . . . .(him 10 years ago) is (wife now)
. . . . .(him now) is (twice) (wife 10 years ago)

Translate these relationships into two equations. Then solve the system of equations for the two values.

:D

zackattack
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Re: Ten years ago a man was as old as his wife is now.

Postby zackattack » Sat Apr 04, 2009 10:57 pm

so its (h-10)=(w) and (h)=2(w-10)?
i get w=30 h=40 is that rite?

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stapel_eliz
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Postby stapel_eliz » Sat Apr 04, 2009 11:57 pm

zackattack wrote:so its (h-10)=(w) and (h)=2(w-10)?
i get w=30 h=40 is that rite?

You can check the answer to any "solving" exercise by plugging your solution back into the original problem, and seeing if it works. In your case:

If he's currently forty and she's currently thirty, then how old was he, ten years ago? How does this compare with her current age?

If she's currently thirty, how old was she, ten years ago? What is twice this value? How does this compare with his age now?

:wink:

stilllearning
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Re: Ten years ago a man was as old as his wife is now.

Postby stilllearning » Mon Apr 06, 2009 12:29 am

Well, I used substitution and I got
husband's age = 40
wife's age = 30


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