An empty cistern has three pipes A, B and C. A and B can fil it in 5 hours and 6 hours respectively and C can empty it in 2 hours. If these pipes are opened in order at 1 a.m., 2 a.m. and 3 a.m., when
will the cistern be empty again?
(a) 3hr after 3 a.m.
(b) 6 hr after 3 a.m.
(c) 7 1/4hr after 3 a.m.
(d) 8 hr after 3 a.m.
Answers
Step-by-step explanation:
Answer
Let us name the 3 Taps be TA,TB,TC
where TB,TC are emptying pipes and TAis filling Pipe.
Water Supplied by TA in 3 hours=Volume of Tank or V
Water Supplied by TA in 1 Hour=3V
Similarly, Water Supplied by TB in 4 Hour=V
Water Supplied by TB in 1 Hour=4V
Using Given Information
⇒3V−CV=−V
Solving,we get
⇒C=43
where C is the Time taken by TC to empty the Full Tank Alone
So, Water Emptied by TC in 43 Hour=
Answer
Let us name the 3 Taps be TA,TB,TC
where TB,TC are emptying pipes and TAis filling Pipe.
Water Supplied by TA in 3 hours=Volume of Tank or V
Water Supplied by TA in 1 Hour=3V
Similarly, Water Supplied by TB in 4 Hour=V
Water Supplied by TB in 1 Hour=4V
Using Given Information
⇒3V−CV=−V
Solving,we get
⇒C=43
where C is the Time taken by TC to empty the Full Tank Alone
So, Water Emptied by TC in 43 Hour=V
Water Emptied by TC in 1 H