A real estate agent did research to compile the number of new home sales in five different cities, for each of the years 2004, 2006, 2008, and 2010. Each number indicates the total number of new homes sold in that city in that year, regardless of when construction started on each home.
From the drop-down menu, select the option that creates the most accurate statement based on the information provided.
Q) The city with the greatest variance in new home sales during the 4 years is
is a measure of how far data points of a dataset are spread w.r.t. mean.
We are interested in fetching a single value as variance that will be a representative value for all deviations of the data points. As a thumb rule, more the spread (range) of data points from mean value, more the variance could be and vice versa. there are exception to this.
Here, you should apply your best estimation - which variance value would be greater than the other? It is quite obvious that project Antioch will have the highest value of variance among all projects, because it has the highest range (350-50=300) among all projects. The three extreme data points (350, 50 and 50) will increase the values of deviations to higher level. So the answer is Antioch.
Hope this helps.
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