Two pipes a and b can separately fill a cistern in 10 and 15 minutes respectively. A person opens both the pipes together when the cistern should have been was full he finds the waste pipe open. He then closes the waste pipe and in another 3 minutes the cistern was full. In what time can the waste pipe empty the cistern when fill ?
Answers
Answer:
Step-by-step explanation:
Hello there,
If any doubt in the following explanation, feel free to ask!
Thank you.
waste pipe can empty the cistern in 12 mins when full
Step-by-step explanation:
Two pipes a and b can separately fill a cistern in 10 and 15 minutes respectively.
pipe a can fill in 1 min = 1/10
pipe b can fill in 1 min = 1/15
pipe a & b together can fill in 1 min = 1/10 + 1/15
=(3 + 2)/30
= 5/30
= 1/6
a & b can fill in 6 mins
after 6 mins waste pipe closed and
then in another 3 mins cistern filled
so in 3 mins a & b can fill = 3 * 1/6 = 1/2
so in first 6 mins filled = 1 - 1/2 = 1/2
in 6 min emptied by waste pipe = 1 - 1/2 = 1/2
=>in 1 min waste pipe can empty = 1/12
waste pipe can empty the cistern in 12 mins when full
Learn more:
14. Pipes A, B and C can fill a tank in 12, 15 and 20 ...
https://brainly.in/question/12746195
If two pipes function simultaneously, the reservoir will be filled in 12 ...
https://brainly.in/question/8254975
Two pipes a and b can fill an empty cistern in 18 and 27 hours ...
https://brainly.in/question/8502414