SOLUTION: One painter can paint 3 pictures in 60 minutes. Another can paint 5 pictures in 75 minutes. If both work together, how long will it take them to paint 7 pictures?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: One painter can paint 3 pictures in 60 minutes. Another can paint 5 pictures in 75 minutes. If both work together, how long will it take them to paint 7 pictures?      Log On


   



Question 508937: One painter can paint 3 pictures in 60 minutes. Another can paint 5 pictures in 75 minutes. If both work together, how long will it take them to paint 7 pictures?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
One painter can paint 3 pictures in 60 minutes. Another can paint 5 pictures in 75 minutes. If both work together, how long will it take them to paint 7 pictures?
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1st painter DATA:
rate = 1/20 job/min
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2nd painter DATA:
rate = 1/15 job/min
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Together DATA:
rate = 1/x job/min
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Equation:
rate + rate = together rate
1/20 + 1/15 = 1/x
Multiply thru by 60x to get:
3x + 4x = 60
7x = 60
x = 60/7 = 8 4/7 minutes (time to paint 1 picture together)
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Ans: time to paint 3 pics together = 3(60/7) = 25 5/7 minutes
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Cheers,
Stan H.