Stats: Simple Weighted Means Question

[shawnz1102]

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:

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

Fat (g/oz)
3.33
3.00
2.50
4.40
1.75

Would Meat/Fish be the weight, or would fat (g/oz) be the weight, and why?

 

[mathman]

[Σ(meat/fish)xfat]/Σ(meat/fish) is the answer.
[10+9+5+11+7]/[3+3+2+2.5+4]

 

[shawnz1102]

[Σ(meat/fish)xfat]/Σ(meat/fish) is the answer.
[10+9+5+11+7]/[3+3+2+2.5+4]

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.

 

[mathman]

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.