1.

Pipe A and pipe B can fill up a tank in 40 min and 80 min respectively. Both the pipes are opened simultaneously for some time and pipe B is closed. If the total time to fill up the tank is 30 minutes, then how long the pipe B was open for?

A. 5 min
B. 10 min
C. 15 min
D. 20 min
Answer» E.


Discussion

No Comment Found

Related MCQs