<PRE><B>Question 473474</B>
Bret can plow his driveway in eight hours, his neighbor can plow his driveway in 12 hours, how long will it take if they do it together?
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Bret rate: 1/8 job/hr
Neighbor rate: 1/12 job/hr
Together rate: 1/x job/hr
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Equation:
rate + rate = together rate
1/8 + 1/12 = 1/x
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(8+12)/(8*12) = 1/x
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20x = 96
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x = 4.8 hr. = 4hr 48minutes (for them to do the job together)
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Cheers,
Stan H.</PRE>