- A3.7 h
- B3 h
- C4 h
- D3.75 h
Step-by-Step Solution
In 30ths: hour 1 A gives 5; hour 2 A + B give 8 (total 13). Then all three give 10 per hour, so 17 more takes 1.7 h. Total 3.7 h. (3 h is all three from the start.)
Answer: A) 3.7 h
Pipes A, B and C fill a tank in 6, 10 and 15 hours. A is opened alone at first; after 1 hour B is opened, and after one more hour C is opened as well. In how many hours from the start is the tank full?
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