Question 381940
Rob 4 hours
Darrin 3 hours
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Rob does 1/4 of the job in 1 hour
Darrin does1/3 of the job in 1 hour.
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both together will do 1/4 +1/3 of the job in 1 hour
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1/4 +1/3 = 7/12 of the job in 1 hour.
they will take 12 /7 hours to do the job together.
=1.7 hours
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m.ananth@hotmail.ca