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2 taps A and B can fill a bucket in 12 and 18 minutes resp. How long will it take both...
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Best answer as selected by question asker.
With the tap A is running alone the bucket is filled in 12 minutes and when tap B alone is running the bucket is filled in 18 minutes.
The rate at which tap A can fill the bucket is 1/12 per minute. The rate at which tap B can fill the bucket is 1/18 per minute.
When both the taps are running the bucket is filled at the rate 1/12 + 1/18 = 5/36
To fill the bucket it takes 36/5 = 7.2 minutes
The bucket is filled in 7.2 minutes when both the taps are running.
Posted by justaguide on June 12, 2011 at 4:33 PM (Answer #1)
High School Teacher
We can also set up an equation to solve this work problem.
We are given that tap A can fill a bucket by itself in 12 minutes and tap B can fill the bucket in 18 minutes. We are asked how long it will take for the two taps running together to fill the bucket.
=> let x = total job time for both working together
=> let 1/12x = time it takes for tap A to fill the bucket
=> let 1/18x = time it takes for tap B to fill the bucket
=> The entire completion of the job will be equal to 1
=> 1/12 x + 1/18x = 1 (completed job)
=> 36 [1/12 x + 1/18x = 1] (to clear fractions)
=> 3x + 2x = 36
=> 5x = 36
=> x =36/5 or 7.2 minutes
Both taps running together will fill the bucket in 7.2 minutes.
Posted by academicsfirst on June 12, 2011 at 6:27 PM (Answer #2)
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