Think of the amount done in 1 hour Together they do 1/7th of the work. The fraction A alone would in 1 hour is 1/x and for B it would be 1/(x+6)

Hence together in 1 hour the fraction they would do would be 1/x+1/(x+6) which therefore =1/7

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- April 17th 2012, 04:53 AM #1

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## (1/(x+6))+(1/x)=(1/7)

**Word Problem:**Two companies working together can clear a parcel of land in 7 hours. Working alone, it would take**Company A**6 hours longer to clear the land than it would**Company B**. How long would it take**Company B**to clear the parcel of land alone?

This is what I did:

**Company A:**x+6

**Company B:**x

Then it asked me to make an equation out of it. My answers we're all wrong, so I gave up and looked for the answer. And this is what they said:

**** Can somebody explain to me why the numerators are 1s?**

I got this far:**x²-8x-42=0**

Then, says I have to use the Quadratic Formula.

Tried to solve it but I always end up with a radical.. which is:**(8±2√58)/2**

and if simplified, would be (?):**4±√58**

I re-checked several times but I cannot see what I did wrong..

I appreciate any help.

Thank You,

Azusa.

- April 17th 2012, 05:23 AM #2

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## Re: (1/(x+6))+(1/x)=(1/7)

Think of the amount done in 1 hour Together they do 1/7th of the work. The fraction A alone would in 1 hour is 1/x and for B it would be 1/(x+6)

Hence together in 1 hour the fraction they would do would be 1/x+1/(x+6) which therefore =1/7

- April 17th 2012, 05:40 AM #3

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- April 17th 2012, 06:37 AM #4

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- April 17th 2012, 06:50 AM #5

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