Question 435215
If paul takes 10hours to paint a house , and wiliam takes 5 hours to paint the same house. how much time it will take them to paint the house if they work together ???
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Paul's rate: 1/10 job/hr
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William's rate: 1/5 job/hr
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Together rate: 1/x job/hr
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Equation:
rate + rate = together rate
1/10 + 1/5 = 1/x
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Multiply thru by 10x:
x + 2x = 10
3x = 10
x = 3 1/3 hrs = 3 hr 20 min (time to do the job together)
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Cheers,
Stan H.