Just Enough Stats for the SAT
You want to go to college but maybe math is not your thing and maybe you’ve never had a chance to learn much of statistics. But still you need to make a decent showing on the SAT. You don’t have time to go down the rabbit hole of a full stats course but you do need some statistics for SAT prep. If that’s you, you’ve come to the right page.
I’ve reviewed the stats questions in the math sections of The Official SAT Study Guide, 2016 edition, to see just what is likely to come up. That is covered on this page.
Solution. Remember that standard deviation measures the extent to which data are spread out. That is determined by two things: the range (the difference between the greatest number and the least) and the way the numbers are distributed within the range. More data near the extremes of the range means a higher standard deviation. For this problem, the range is the same for both stores, so any difference in standard deviation will come from the distribution of those numbers within the set. Note that in store A the greatest numbers of packages are near the center of the range and at store B the greatest numbers are at the ends of the range. So the data set for store B has the higher standard deviation. (p. 721, #23)