stated problem: A father's age is 4 times that of his son.

Simplificatation, evaluation, linear equations, linear graphs, linear inequalities, basic word problems, etc.
Motherof8
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stated problem: A father's age is 4 times that of his son.

Postby Motherof8 » Thu Aug 25, 2011 12:40 am

A father's age is 4 times that of his son. 4 years ago it was 6 times as great. Find their ages. I said the son's age was x, and the father's age was 4x. Then I wrote this equation: 4x-4 =6x, but the answer doesn't make sense.

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stapel_eliz
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Postby stapel_eliz » Thu Aug 25, 2011 11:24 am

Motherof8 wrote:A father's age is 4 times that of his son. 4 years ago it was 6 times as great. Find their ages. I said the son's age was x, and the father's age was 4x. Then I wrote this equation: 4x-4 =6x....

The expression "4x - 4" is "the father's age, four years ago". The expression "6x" is "six times the son's age now". Is this what the exercise means, or does it mean "six times the son's age then"? :wink:

Motherof8
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Re: stated problem: A father's age is 4 times that of his so

Postby Motherof8 » Thu Aug 25, 2011 3:16 pm

Now that I reaad it again, I think it means 6 times his aage then.

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stapel_eliz
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Postby stapel_eliz » Thu Aug 25, 2011 5:49 pm

Motherof8 wrote:Now that I reaad it again, I think it means 6 times his aage then.

So, following the set-up logic explained here, you have the following:

. . .ages now:
. . . . .son: x
. . . . .father: 4x

. . .ages then:
. . . . .son: ??
. . . . .father: 4x - 4

Complete the table, and then insert the appropriate bits into the sentence:

. . . . .(father's age then) was (six)times (son's age then)

Then solve the equation. :wink:


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