7000B= 100000- 9000*8superrrom wrote:Thanks
7000b = 28000
hence b takes 28000/7000 hr = 4
hope that helps..
work/rate
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sudhir3127
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7000b = 28000
hence b takes 28000/7000 hr = 4
hope that helps..
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II
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I used similar approach as Sudhir here. Just to add some more explanation ...
Question is asking to us find out the least amount of time that Machine B needs to work. We know that the maximum working time is 8 hours ... so if Machine A worked for for its maximum time: 8 hours, then it would have produced 9000*8 = 72000 pencils.
This leaves 28000 pencils to be produced (100000-72000).
From this we can work out how long machine B needs to work.
RT = W
T = W/R
T = 28000/7000
T = 4
Question is asking to us find out the least amount of time that Machine B needs to work. We know that the maximum working time is 8 hours ... so if Machine A worked for for its maximum time: 8 hours, then it would have produced 9000*8 = 72000 pencils.
This leaves 28000 pencils to be produced (100000-72000).
From this we can work out how long machine B needs to work.
RT = W
T = W/R
T = 28000/7000
T = 4
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canuckclint
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You want to maximize A's production and work it for 8 hours.
9000 * 8 will produce 72,000 pencils.
72,000 + 7000 * TimeB = 100,000
TimeB = 4 hours
9000 * 8 will produce 72,000 pencils.
72,000 + 7000 * TimeB = 100,000
TimeB = 4 hours
