Question
Sneha and Meena can complete a project in 24 days and 60
days respectively. Sneha began working first. After how many days should Meena step in so that the project is completed in 20 days?Solution
ATQ,
Let the total work be 120 units (LCM of 24 and 60)
Efficiency of Sneha = (120 / 24) = 5 units/day
Efficiency of Meena = (120 / 60) = 2 units/day
Let Meena join after 'n' days.
So, 5n + (5 + 2) × (20 - n) = 120
⇒ 5n + 140 - 7n = 120
⇒ 2n = 20
⇒ n = 10
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