Question
‘A’ takes 20 days to do some work. If ‘B’ is 20%
more efficient than ‘A’, then find the time taken by them to finish 99% of the work together.Solution
Let the work by 100x units.
Efficiency of ‘A’ = 100x ÷ 20 = ‘5x’ units/day
Efficiency of ‘B’ = 5x × 1.2 = ‘6x’ units/day
99% of the work = 100x × 0.99 = 99x units
Required time = 99x ÷ (5x + 6x) = 9 days.
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