CSATTime & WorkTime and Work2024

X, Y and Z can complete a piece of work individually in 6 hours, 8 hours and 8 hours respectively. However, only one person at a time can work in each hour and nobody can work for two consecutive hours. All are engaged to finish the work. What is the minimum amount of time that they will take to finish the work?

(a) 6 hours 15 minutes

(b) 6 hours 30 minutes

(d) 7 hours

Correct Answer: Option C

Explanation

1. **Define Work in Units (LCM Method)** [20]: - Times are 6, 8, and 8 hours. - Let Total Work = LCM(6, 8, 8) = **24 units**. - Efficiency of X = 24/6 = **4 units/hr**. - Efficiency of Y = 24/8 = **3 units/hr**. - Efficiency of

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