Two pipes A and B can fill a cistern in 37 1/2 minutes and 45 minutes respectively. Both pipes are opened. The cistern will be filled in just half an hour, if the pipe B is turned off after?

A. 15 min

B. 9 min

C. 5 min

D. 10 min

Be the first to comment if anything wrong with this mcq
Your comment successfully submitted!
It will automatically posted after review and approval by our staff member.