Question
24 delivery boys can complete a delivery in 15 days. If
12 boys start the same work, and after 12 days, 'd' more boys join the work, completing the remaining task in the next 12 days, find the value of 'd'. (All boys have the same efficiency.)Solution
ATQ, Total work = 24 × 15 = 360 units Amount of deliveries completed by 12 men in 12 days = 12 × 12 = 144 units Amount of work to be completed by (12 + d) men = 360 – 144 = 216 units Therefore, (12 + d) × 12 = 216 Or, 12 + d = 18 Or, d = 6
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