3 men and 5 boys can complete a task in 15 days, whereas 6 men and 7 boys can complete the same task in 9 days. Find the relationship between the task done by the boys and the task done by the men.
3 men and 5 boys can complete a task in 15 days, whereas 6 men and 7 boys can complete the same task in 9 days. Find the relationship between the task done by the boys and the task done by the men. Correct Answer The work of 4 boys is equivalent to the work of 3 men
Let efficiency of 1 man and 1 boy be x and y respectively,
According to the question
(3x + 5y) × 15 = (6x + 7y) × 9
⇒ 45x + 75y = 54x + 63y
⇒ 54x – 45x = 75y – 63y
⇒ 9x = 12y
⇒ x : y = 4 : 3 ----(i)
Let’s check the option
Option 1: 3x = 4y
From (i), we get
3 × 4 = 4 × 3
⇒ 12 = 12
∴ Option 1 is correct
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Feb 20, 2025