Question
20 men working 6 hours a day can paint a building in 25
days. If 30 men work 8 hours a day, how many days will it take to paint the building?Solution
ATQ,
Let the efficiency of a man = 'x' units/hour
Total work = 20 × x × 6 × 25 = 3000x units
Number of days taken by 30 men working 8 hours/day =
= 3000x ÷ (30 × x × 8)
= 3000x ÷ 240x = 12.5 days
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