A cistern has three pipes, A, B and C.
A cistern has three pipes, A, B and C. The pipes A and B can fill it in 5 and 6hours respectively and C can empty it in 2 hours. If the pipes are opened in order at 1, 2 and 3 A.M. When will the cistern be empty?
Answer/Solution
7hrs 15 min. (AM)
Steps/Work
1 to 2 = 1/5
2 to 3 = 1/5 + 1/6 = 11/30
After 3 AM = 1/5 + 1/6 - 1/2= -4/30
1/5 + 11/30 = 17/30
1 h ---- 4/30
? ----- 17/30
7hrs 15 min. (AM)
Answer:D
2 to 3 = 1/5 + 1/6 = 11/30
After 3 AM = 1/5 + 1/6 - 1/2= -4/30
1/5 + 11/30 = 17/30
1 h ---- 4/30
? ----- 17/30
7hrs 15 min. (AM)
Answer:D