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You are not logged in. #1 20130407 03:38:06
Weighted averagesHow would you find the weighted average of example 14 different countries with different unemployment rates? #2 20130407 03:41:05
Re: Weighted averagesHi; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #3 20130407 03:42:48
Re: Weighted averagesWeighted Average of the countries = ((Frequency 1)*(Rate 1) + (Frequency 2)*(Rate 2) + ...)/14 'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.' 'God exists because Mathematics is consistent, and the devil exists because we cannot prove it' 'Who are you to judge everything?' Alokananda #4 20130407 03:53:21
Re: Weighted averagesHey there #5 20130407 03:56:23
Re: Weighted averagesjust add 'em up and divide by 14 'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.' 'God exists because Mathematics is consistent, and the devil exists because we cannot prove it' 'Who are you to judge everything?' Alokananda #6 20130407 04:09:32
Re: Weighted averagesI have been trying that, but not getting to 8.2 #7 20130407 04:10:45
Re: Weighted averagesI do not think you are providing everything. Where are the weights? In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #8 20130407 04:15:33
Re: Weighted averagesHi clueless101, "Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  Buddha? "Data! Data! Data!" he cried impatiently. "I can't make bricks without clay." #9 20130407 04:23:34
Re: Weighted averagesThe book only gives me the country names and the unemployment rates #10 20130407 04:25:55
Re: Weighted averagesHi; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #11 20130407 04:38:51
Re: Weighted averagesThey do mention that the weights are necessary since the populations of the countries are different. If they were all equal the average would be the sum of all percentages divided by 14. #12 20130407 04:40:10
Re: Weighted averagesMaybe they want you to look up the populations of the countries. In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #13 20130407 04:44:57
Re: Weighted averagesYes that's the weight that is needed. If you weren't given them, you'll have to look them up. simple example to show why you have to do this. Suppose country A has 1000 people and 100 are unemployed. That's 10% unemployed. Suppose country B has 10 people and 9 are unemployed. That's 90% unemployed. If you just do (10 + 90)/2 = 50, you've given too much importance to country B You need to go back to the raw data. Total population = 1000 + 10 = 1010 Total unemployed = 109. So true average = 109/1010 x 100 = 10.8% The answer is properly weighted towards the larger population. Using the formula {(1000 x 10) + (10 x 90)} / 1010 = 10.8 Bob You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei 