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Answer: (C) 2 52 73
Explanation
To find the time taken when A, B, and C work together, we use the work-rate formula where the combined rate is the sum of individual rates: 1/T = 1/T_A + 1/T_B + 1/T_C. Substituting the given values, the combined rate is 1/6 + 1/9 + 1/11. The Least Common Multiple (LCM) of 6, 9, and 11 is 198, which we use as the total units of work.
The individual efficiencies are calculated by dividing the total work by each person's time: A produces 198 / 6 = 33 units per day, B produces 198 / 9 = 22 units per day, and C produces 198 / 11 = 18 units per day. The total efficiency of all three working together is 33 + 22 + 18 = 73 units per day.
The time required to complete the work is the total work divided by the total efficiency: T = 198 / 73. Dividing 198 by 73 gives a quotient of 2 and a remainder of 52. This can be written as the mixed fraction 2 ⁵²⁄₇₃. Match this result to the provided options where the mixed fraction is represented as 2 52 73.