Question
Working 6 hours a day, Rahul can complete a work in 25
days. How many hours a day should he work to complete the same work in 15 days?Solution
ATQ,
Let the efficiency of Rahul be 'x' units per hour
Therefore, total work = 6 × 25 × x = 150x units
Let the time he should work to complete the work in 15 days be 'y' hours a day.
ATQ;
150x = 15 × y × x
Or, y = 10
Therefore, he should work for 10 hours a day.
Alternate solution:
Required time = (6 × 25) ÷ 15 = 10 hours
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