SOLUTION: If it takes 2hours using 20pumps to drain a pool,and 4hours using 10pumps,and 8hours using 5pumps to drain the same pool,how long will it take to drain the pool using 16pumps?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: If it takes 2hours using 20pumps to drain a pool,and 4hours using 10pumps,and 8hours using 5pumps to drain the same pool,how long will it take to drain the pool using 16pumps?      Log On


   



Question 896535: If it takes 2hours using 20pumps to drain a pool,and 4hours using 10pumps,and 8hours using 5pumps to drain the same pool,how long will it take to drain the pool using 16pumps?
Found 2 solutions by JulietG, stanbon:
Answer by JulietG(1812) About Me  (Show Source):
You can put this solution on YOUR website!
Do you see the pattern?
2 20
4 10
8 5
16 ?
(hint: doubling the pumps yields half of the previous time)

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If it takes 2hours using 20pumps to drain a pool,and 4hours using 10pumps,and 8hours using 5pumps to drain the same pool,how long will it take to drain the pool using 16pumps?
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time is inversely related to # of pumps.
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t = k/p
Solve for "k":
2 = k/20
k = 40
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Equation:
t = 40/p
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Your Problem:
t = 40/16
t = 5/2 = 2 1/2 hours
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Cheers,
Stan H.