Question 10
A cistern can be filled by pipe $A$ in 20 hours while it can be emptied by pipe $B$ in 30 hours.
a) If both pipes are opened simultaneously, find the time taken to fill the cistern.
b) If $A$ is opened first, after 10 hours, pipe $B$ is also opened. Find the total time taken to fill the whole tank.
a) If both pipes are opened simultaneously, find the time taken to fill the cistern.
b) If $A$ is opened first, after 10 hours, pipe $B$ is also opened. Find the total time taken to fill the whole tank.