How do you calculate a weighted mean?

Question

i know a mean is just the total of a series divided by the number of figures in a series, however this can be distorted by high figures at the extremes for instance for house prices say 15 people may have houses worth around 100k and say 2 have houses worth over 1 million then by simply adding up the total value of all the houses divided by the total number of houses in this case 17 the figures will give an average but will be distorted by the two people whoose houses are worth around a million how do i calculate the weighted mean? pleassssssssse Help...

Answer 1

Your problem is a common one. The average income and wealth in several places in the US, the home of Google, Microsoft etc, average wealth is strongly influenced by a few people. One solution is to use the median or to break in into quintiles(1/5) and give the average of each portion. There is no way to weight it.

Answer 2

when you are asked for a weighted mean you are usually give the weights....the question above would not be used for a weighted mean unless you weighted houses within a radius of something...weighted means are usually used for inventory and such

Answer 3

Add up the total number of people enrolled, that is, all the people in all the sections.. Multiply the enrollment of a section by its average score, and do it for each section. Add them all up, then divide by the total number.