2013 · Q79
Pipe A can fill a tank in 10 minutes and pipe B can empty it in 15 minutes. If both the pipes are opened in an empty tank, the time taken to make it full is
Elementary MathematicsArithmetic
- A20 min
- B25 min
- C30 min
- DNone of the above
Explanation
1/10−1/15=1/30 → 30 min. Answer C.