Description:
Statistical Figure questions require you to interpret data from a figure
in order to answer a question. These questions rarely require more than
arithmetic, but they often present the data in a less than straightforward manner.
Approach:
Read the information carefully: pay attention to units, keys, and labels.
1) Percent Change and Change are not the same thing
In order to calculate the percent change in two values on a chart or
graph, you have to divide the change between the two values by the
starting value. For example if Tom was 5 feet tall at 13 and 6 feet tall
at 18, the percent change in his height for the 5 years would be:
(6 - 5) ⁄ 5
= 0.20, or 20%.
2) Percent and Degrees do not have the same value in a pie chart
Often, the SAT will give you
pie chart values in percentages, and then
ask you for the number of degrees in one of the sectors of the pie
chart. Make sure you convert the remaining percentage into degrees
using the following proportion:
Percent ⁄ 100 =
Degrees ⁄ 360
3) Practice:
-
If a company's stock price was $20 in January and $30 in March, what was
the percent change in the stock price during the
period?
-
If Mark was 60 inches tall when he was 13 and 72 inches tall when he was 16,
what was the percent change in Mark's height during the three year period?
