- A3 h
- B1.2 h
- C2 h
- D4 h
Step-by-Step Solution
First pipe: . The second filled , i.e. ran h. So the first worked alone h. (4 h is how long the second ran.)
Answer: C) 2 h
A pipe can fill a tank in 12 hours. It worked alone for a while, then a second pipe that fills the tank in 8 hours joined it, and the tank was full 6 hours after the first pipe started. How long did the first pipe work alone?
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