Question
A can do a work in 45 days and the same the work is
done in 15 days by A and B together, then in how many days B can complete the 20% of work?Solution
A takes 45 days A and B together takes 15 days LCM of 45 and 15 = 45 units Efficiency of A = 45/45 = 1 Efficiency of A and B = 45/15 = 3  So, efficiency of B = 3 – 1 = 2 B does 20% of the total work. Then, 20% of 45 = 9 units So, B will take 9/2 = 4.5 days to complete the work.
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