- A6
- B24.5
- C35
- D5
Step-by-Step Solution
Combined rate = 1/7 + 1/42 = (6 + 1)/42 = 1/6 of the ground per hour, so 6 hours.
Answer: A) 6
Mehul can sweep the school playground in 7 hours, and the elderly caretaker takes 42 hours to do it alone. If they sweep it together, how many hours will it take?
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