Question
'A' alone can do some work in 12 days. 'B' is 50% more
efficient than 'A'. 'A' worked alone for 3 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' = 1.5x units/day.
Total work = 12 × x = 12x units.
Work done by 'A' in three days = 3 × x = 3x units.
Remaining work = 12x − 3x = 9x units.
Time taken by 'B' to finish the remaining work = ({9x/1.5x} = 6) days.
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