SOLUTION: 1. A scanner can read a stack of sheets in 20 minutes. A second scanner can read the same stack in 12 minutes. How much time would it take for both scanners together to process th
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-> SOLUTION: 1. A scanner can read a stack of sheets in 20 minutes. A second scanner can read the same stack in 12 minutes. How much time would it take for both scanners together to process th
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Question 1161170: 1. A scanner can read a stack of sheets in 20 minutes. A second scanner can read the same stack in 12 minutes. How much time would it take for both scanners together to process the one stack of sheets?
My answer is 8 minutes - is that correct?
2. A laborer can do a certain job in 5 days, a second can do the job in 6 days, and a third in 8 days. In what time can the three together do the job?
My answer is 2 days - is that also correct?
Thank you. Answer by ikleyn(52803) (Show Source):
First scanner makes of the job per minute.
Second scanner makes of the job per minute.
Working together, they make = = of the job per minute.
Hence, it will take = = 7.5 minutes for two scanners to complete the job working together.
