Two pipes A and B can fill a tank in 4 and 5 hours respectively. If they are turned up alternately for one hour each, the time taken to fill the tank is?
A. 2 hrs 15 min
B. 4 hrs 24 min
C. 5 hrs
D. 3 hrs
Answer:B
Two pipes A and B can fill a tank in 4 and 5 hours respectively. If they are turned up alternately for one hour each, the time taken to fill the tank is?
A. 2 hrs 15 min B. 4 hrs 24 min C. 5 hrs D. 3 hrs