Magoosh
Working together, 7 identical pumps can empty a pool in 6 hours. How many hours will it take 4 pumps to empty the same pool?
A. 4 2/3
B. 9 1/4
C. 9 1/3
D. 9 3/4
E. 10 1/2
OA E
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Working together, 7 identical pumps can empty a pool in 6 hours. How many hours will it take 4 pumps to empty the same
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ASISHSINGH
- Newbie | Next Rank: 10 Posts
- Posts: 1
- Joined: Sat May 01, 2021 2:14 am
Let the total amount of work required =42 units
In 6 hours work done =42 hours => so each hour work done =42/6 =7 unit /hr
since 7 pumps are working so total 1unit work per hour is done by each pump.
Hence 4 pumps will do 4 unit of work per hour
Total time required =42/4=21/2=10 1/2
Hence E.
In 6 hours work done =42 hours => so each hour work done =42/6 =7 unit /hr
since 7 pumps are working so total 1unit work per hour is done by each pump.
Hence 4 pumps will do 4 unit of work per hour
Total time required =42/4=21/2=10 1/2
Hence E.
