Question
"A" can complete a task in 15 days, while it takes 25
days for "B" to complete the same task. The ratio of the efficiencies of "A" and "C" is 2:1. If a task takes 30 days for 2A, 3B, and 4C working together, find out the number of tasks that were achieved.Solution
ATQ, Let the total number of task achieved be ‘a’ and each Task are of 300b units of work. Efficiency of a 'A'= 300b/15 = 20b units/day Efficiency of a 'B' = 300b/25 = 12b units/day Efficiency of a 'C' = (1/2) × 20b = 10b units/day Now, total task achieved = a × 300b units Work done by 2A, 3B and 4C working together in 30days = 30 × (2 × 20b + 3 × 12b + 4 × 10b) units = 30 × (40b + 36b + 40b) units = 3480b units ATQ, a × 300b = 3480b Or, a = 3480/300 = 11.6
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