- A7.5
- B15
- C8
- D2
Step-by-Step Solution
Net rate = 1/3 − 1/5 = 5/15 − 3/15 = 2/15 tank per hour, so time = 15/2 = 7.5 hours.
Answer: A) 7.5
A pipe can fill a tank in 3 hours, and a drain pipe can empty the full tank in 5 hours. If both are opened together on an empty tank, in how many hours will it be filled?
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