Question
A, B, and C together can do a work alone in 13 days, 52
days, and 91 days respectively. A alone starts the work and work for 3 days and leaves the work, then B alone does the work for 8 days and leaves the work. If remaining work is done by C alone then for how many days has C worked?Solution
Total work = LCM of 13, 52 and 91 = 364 units Unit per day of A = 364/13 = 28 Unit per day of B = 364/52 = 7 Unit per day of C = 364/91 = 4 Units of work done by A in 3 days = 28 × 3 = 84 units Units of work done by B in 8 days = 7 × 8 = 56 units Remaining work = 364 – (84 + 56) = 224 units So, C has worked for 224/4 = 56 days
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