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Stats: Simple Weighted Means Question

  1. Sep 12, 2010 #1
    Hey guys, this is for an elementary statistics course. When given a problem, I am having trouble determining which is the data set (X) and which is the weight (W).

    For example:

    Using the weighted mean, find the average number of grams of fat per ounce of meat or fish that a person would consume over a 5-day period if he ate these:

    3 oz. fried shrimp
    3 oz. veal cutlet
    2 oz. roast beef
    2.5 oz fried chicken drumbstick
    4 oz tuna

    Fat (g/oz)

    Would Meat/Fish be the weight, or would fat (g/oz) be the weight, and why?
  2. jcsd
  3. Sep 13, 2010 #2


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    Science Advisor

    [Σ(meat/fish)xfat]/Σ(meat/fish) is the answer.
  4. Sep 14, 2010 #3
    Yep, but I want to know for future reference how to determine which set of data should be the mean, and which set of data should be the weight.
  5. Sep 14, 2010 #4


    User Avatar
    Science Advisor

    I am not sure how to answer your question. In your case "fat" is the function and "meat/fish" is the weight. The mean is the answer.
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