Question 774976
Joe seals a driveway in 4hrs.
So Joe seals 1/4 of the driveway in 1hr.
Let Louis seal the driveway in 'x'hrs.
So Louis seals 1/x of the driveway in 1hr.
Joe and Louis together seal the same driveway in 2.3hrs.
So they together seal 1/2.3 of the driveway in 1hr.
Therefore we can write 1/4 + 1/x = 1/2.3 ---------------------(1)
or 1/x = 1/2.3 - 1/4 = 0.43478 - 0.25 = 0.18478
or x= 1/0.18478 = 5.4(approx.)
So Louis can seal the driveway alone in 5.4hrs.(approx.)