SOLUTION: If Sally can paint a house in 4 hours, and John can paint the same house in 6 hour, how long will it take for both of them to paint the house together? How do I set this up to so

Algebra ->  Equations -> SOLUTION: If Sally can paint a house in 4 hours, and John can paint the same house in 6 hour, how long will it take for both of them to paint the house together? How do I set this up to so      Log On


   



Question 514340: If Sally can paint a house in 4 hours, and John can paint the same house in 6 hour, how long will it take for both of them to paint the house together?
How do I set this up to solve it?

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If Sally can paint a house in 4 hours, and John can paint the same house in 6 hour, how long will it take for both of them to paint the house together?
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Sally rate = 1/4 job/hr
John rate = 1/6 job/hr
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Together rate: 1/x job/hr
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Equation:
rate + rate + together rate
1/4 + 1/6 = 1/x
Multiply thru by 12x:
3x + 2x = 12
5x = 12
x = 2.4 hr = 2hr 24 min (time to do the job together)
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Cheers,
Stan H.