Question
P and Q individually can complete a work in 20 days and
30 days respectively. If the time taken by R alone to complete the work is 1.5 times the time taken by P and Q together to complete the work, find the time taken by R to complete the work while working alone.Solution
Time taken by P and Q together to complete the work = (20 × 30)/ (20 + 30) = 12 days Time taken by R alone to complete the work = 1.5 × 12 = 18 days
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