Saba, Rayan, and Derin are cooperating to complete a task. When all three work together, it takes 5 minutes to complete the task. How many minutes does it take for Derin to complete the task on his own?
A. 21 B. 28 C. 35 D. 48 E. 105
E
Solving using the rates at which Saba, Rayan, and Derin work gives that Derin takes 105 minutes to complete the task.
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