SOLUTION: If it takes 3 people 4 hours to paint a room, how long will it take 2 people to paint the same room?

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Question 794213: If it takes 3 people 4 hours to paint a room, how long will it take 2 people to paint the same room?
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
So many people painting the room, best is to find the rate of 1 person to paint the room. Then calculate what you want (or are asked).

Recognize, "paint the room" is 1 task. One job.

3 people_______________4 hours______________1 job
(3/3)=1 people___________3*4 hours____________same 1 job

The one-person rate is 12 hours to do the job.
You can express this as 1%2F12 jobs per hour, the one-person rate.

How much time for 2 people to do this one job?
The rates of each person is simply additive.
highlight%282%281%2F12%29%2Ah=1%29 corresponds to rate*hours=jobs and h is a variable for how many hours.

highlight%28h=6%29.
Six hours for two people to paint the room.




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Hopefully, you can intuitively understand that "(3/3)...." line above in the solution and discussion.