- A min
- B min
- C4 min
- D8 min
Step-by-Step Solution
Both open throughout: → min. Earlier by min. (4 min is how long B ran.)
Answer: B) min
Pipe A fills a tank in 15 minutes and pipe B in 20 minutes. Both are opened on the empty tank; after some time B is closed and A finishes, the tank being full 12 minutes after the start. Had B been left open, how many minutes earlier would the tank have filled?
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