Need help with "work" problem

max

Junior Member
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Jun 1, 2007
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50
If x people working at the same rate can complete a job in h hours, what part of the same job can one person working alone complete in k hours?

I havn't seen a work problem like this before.

Can anyone help?
 

Subhotosh Khan

Super Moderator
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Jun 18, 2007
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If x people working at the same rate can complete a job in h hours, what part of the same job can one person working alone complete in k hours?
So

1 person - in h hours - can complete 1/x part of the job

1 person - in 1 hours - can complete 1/(xh) part of the job

Now finish it....
 

max

Junior Member
Joined
Jun 1, 2007
Messages
50
Then the answer would be k/xh

I don't understand the 1/x part. How u do that?

I get the 1 over h part. It would be the same if I said Jack can paint a room in 3 hours that would mean he could paint 1/3 of the room in 1 hour.

I don't get the first part 1/x. What does that mean?

thanks a bunch!
 

Denis

Senior Member
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Feb 17, 2004
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1,459
1/x times h is same as h/x
 

max

Junior Member
Joined
Jun 1, 2007
Messages
50
I think I got it now. I made up a problem using that solving approach. Is my answer right?

If 3 friends can makeover and paint the garage in 3 hours, how long would it take just one of them to do it if the others changed their minds about doing it?

So if 3 can do it in 3 hours
1 can do 1/3 of it in 3 hours
and can do 1/3*3, or 1/9 of it in 1hour
So he can do the whole job in 9 hours.

Is that right?
 

Subhotosh Khan

Super Moderator
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If two (2) people can finish a job - how much each(1) do = 1/2

If two (3) people can finish a job - how much each(1) do = 1/3

If two (4) people can finish a job - how much each(1) do = 1/4

If two (x) people can finish a job - how much each(1) do = 1/x
 

Subhotosh Khan

Super Moderator
Staff member
Joined
Jun 18, 2007
Messages
18,134
If 3 friends can makeover and paint the garage in 3 hours, how long would it take just one of them to do it if the others changed their minds about doing it?

So if 3 can do it in 3 hours
1 can do 1/3 of it in 3 hours
and can do 1/3*3, or 1/9 of it in 1hour
So he can do the whole job in 9 hours.

Is that right?... CORRECT
 
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