Question
A can do a work in 15 days and B in 10 days. They work
together for 3 days. What fraction of the work is left?Solution
ATQ, A's 1 day work = 1/15 B's 1 day work = 1/10 Together in 1 day: 1/15 + 1/10 = 2/30 + 3/30 = 5/30 = 1/6 In 3 days, work done = 3/6 = 1/2 Remaining work = 1 - 1/2 = 1/2
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