1 job work rate of john t work rate of john 1 t notice

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Unformatted text preview: equation to get these rates. æ Work ö æ Time Spent ö 1 Job = ç ÷´ç ÷ è Rate ø è Working ø Let’s start with Machine A. 1 Job = ( Work Rate of A ) ´ ( 5 ) Þ Work Rate of A = 1 5 Þ Work Rate of B = 1 3 Now, Machine B. 1 Job = ( Work Rate of B ) ´ ( 3) Plugging these quantities into the main equation above gives the following equation that we need to solve. 11 Multiplying both sides by 15 t + t =1 53 3t + 5t = 15 8t = 15 15 t = = 1.875 hours 8 So, it looks like it will take the two machines, working together, 1.875 hours to stuff a batch of envelopes. Example 9 Mary can clean an office complex in 5 hours. Working together John and Mary can clean the office complex in 3.5 hours. How long would it take John to clean the office complex by himself? Solution Let t be the amount of time it would take John to clean the office complex by himself. The basic word equation for this problem is, © 2007 Paul Dawkins 77 http://tutorial.math.lamar.edu/terms.aspx College Algebra æ Portion of job ö æ Portion of job ö ç ÷+ç ÷ = 1 Job è done by Mary ø è done by John ø æ Work Rate öæ Time S...
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This note was uploaded on 06/06/2012 for the course ICT 4 taught by Professor Mrvinh during the Spring '12 term at Hanoi University of Technology.

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