
Elementary Math Fractions, Percentages, Word Problems, Equations, Inequations, Factorization, Expansion 
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November 24th, 2014, 02:56 AM  #1 
Senior Member Joined: Oct 2012 From: Live and work in Saudi but from Italy (British national) Posts: 103 Thanks: 2 Math Focus: Hoping to do something in the future.  Lesson on direct and indirect proportion
Hi I have a question: "It takes two electricians 9 days to rewire two house. How long would it take 3 electricians to rewire 3 of the same houses at the same rate?". I dont want the answer. I would like someone to point me to a decent lesson on this subject so I can understand. Any help? Thanks 
November 24th, 2014, 05:34 AM  #2 
Senior Member Joined: Mar 2011 From: Chicago, IL Posts: 214 Thanks: 77 
Let's imagine that the first electrician rewires the first house, and the second electrician rewires the second house. It takes 9 days. Now let's forget second one, and watch just the first electrician. Certainly, it will take 9 days for him to rewire one house. So, 3 electricians rewire 3 houses 9 days, and for any n, it takes n electricians 9 days to rewire n houses. 

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direct, indirect, lesson, proportion 
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