Question
Suppose D, E and F can do a piece of work individually in
18, 27 and 36 days respectively. If they combine and work for 4 days, what percentage of work would be completed?Solution
ATQ,
Let total work be 108 units. {LCM (18, 27, 36)}
Efficiency of D = 108 ÷ 18 = 6 units/day
Efficiency of E = 108 ÷ 27 = 4 units/day
Efficiency of F = 108 ÷ 36 = 3 units/day
Work done in 4 days = 4 × (6 + 4 + 3) = 52 units
Required percentage = (52 ÷ 108) × 100 = 48.15%
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