Question
'A' alone can do some work in 18 days. 'B' is 20% more
efficient than 'A'. 'A' worked alone for 12 days and left. How much time (in days) does 'B' need to finish the remaining work?Solution
Let the efficiency of 'A' be x units/day.
So, efficiency of 'B' = 1.2x units/day.
Total work = 18 × x = 18x units.
Work done by 'A' in twelve days = 12 × x = 12x units.
Remaining work = 18x − 12x = 6x units.
Time taken by 'B' to finish the remaining work = ({6x/1.2x} = 5) days.
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