Question
A is twice efficient as B and B can do a piece of work
in 40 days. B started the work and after a few days A joined him. They completed the work in 32 days. From the starting, for how many days they worked together?Solution
A B Efficiency 2 : 1 B can do this job in 40 days so let total work = 1×40 = 40 units So let A work alone for x days and they work together for remaining i,e. (32-x) Hence 1×x+3(32-x) = 40 x +96 - 3x = 40 56 = 2x So x = 28 days So they work togethr for (32-x) i.e . 4 days
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