SOLUTION: a group of college students are volunteering for help the homeless during spring break. They are putting the finishing touches on a house they built. Working alone, irina can paint

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Question 945152: a group of college students are volunteering for help the homeless during spring break. They are putting the finishing touches on a house they built. Working alone, irina can paint a certain room in 7 hours. Paulo can paint the same room in 6 hours. write an equation that can be used to find how long it will take them working together to paint the room. how many hours will it take them to paint the room?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Working alone, Irina can paint a certain room in 7 hours.
Paulo can paint the same room in 6 hours.
write an equation that can be used to find how long it will take them working together to paint the room.
how many hours will it take them to paint the room?
:
let t = time required when they work together
let the completed job = 1
:
Each will do a fraction of the job, the two fractions add up to 1
t%2F7 + t%2F6 = 1
multiply the equation by the least common multiple of 7&6, 42
42*t%2F7 + 42*t%2F6 = 1*42
cancel the denominators
6t + 7t = 42
13t = 42
t = 42/13
d = 3.23 hrs, which is: 3 + .23(60) = 3 hrs 14 minutes
:
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I'd give the paint and brushes to homeless and let them do it!