SOLUTION: A sewage treatment plant has two inlet pipes to its settling pond. One can fill the pond in 10 hr, the other in 12 hr. If the first pipe is open for 5 hr and then the second pipe
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Question 100266This question is from textbook College Algebra and Trigonometry
: A sewage treatment plant has two inlet pipes to its settling pond. One can fill the pond in 10 hr, the other in 12 hr. If the first pipe is open for 5 hr and then the second pipe is opened, how long will it take to fill the pond? This question is from textbook College Algebra and Trigonometry
You can put this solution on YOUR website! A sewage treatment plant has two inlet pipes to its settling pond. One can fill the pond in 10 hr, the other in 12 hr. If the first pipe is open for 5 hr and then the second pipe is opened, how long will it take to fill the pond?
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1st pipe DATA:
Time to fill = 10 hr/job ; Rate = 1/10 job/hr
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2nd pipe DATA:
Time to fill = 12 hr/job ; Rate = 1/12 job/hr
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EQUATION:(since half of the pond has already been filled)
Let x = time for the two pipe together to fill half the pond
x(1/10 + 1/12) = 1/2
x(22/120)= 1/2
x(11/60) = 1/2
x(11/30) = 1
x = 30/11 = 2 hrs (8/11) hr
(8/11)*60 = 43.6 minutes
Total time for the two pipes to fill half the pond = 2 hrs 43.6 minutes
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Cheers,
Stan H.
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