Question
A man completes a work in 16 days. A woman finishes half of
that work in 10 days. How many days will they take together to finish 75% of the work?Solution
ATQ,
Time taken by the woman to finish the entire work = 10 ÷ 0.5 = 20 days
Let the total work be 80 units. {LCM of (16 and 20)}
So, efficiency of the man = 80 ÷ 16 = 5 units/day
And efficiency of the woman = 80 ÷ 20 = 4 units/day
So, required time = (80 × 0.75) ÷ (5 + 4) = 6.67 days
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