Question
Pooja used to solve 36 problems in 72 minutes. After her
efficiency decreased by 33.33%, how long will she now take to solve the same number of problems?Solution
ATQ,
72 minutes
Initial efficiency = 72 ÷ 36 = 2 minutes/problem
New efficiency = 72 ÷ (36 × 0.6667) = 3 minutes/problem
Time to solve 36 problems = 3 × 36 = 108 minutes
Alternate Solution:
Efficiency ratio = 0.6667:1 = 2:3
Time ratio = 3:2
Required time = 72 × (3/2) = 108 minutes
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