It's a scatter plot, so your data are split across the points (each point is independent and contains its own unique items - it doesn't overlap with any others).
So, you can find the number of items at each price point (for every scatter point, note the y-value) and sum them. This is a bit tedious to do since you'll have 10 values for each store, but it is very obvious from looking at the points that Store 1 will sell more items (their points are higher on average, indicating more items per point).
Mar 20th, 2015
Studypool's Notebank makes it easy to buy and sell old notes, study guides, reviews, etc.