Question

A scatterplot shows the number of hours studied versus test grade.
The horizontal axis shows the number of hours studied, ranging from 0 to 10 in increments of 1. The vertical axis shows the test grade, ranging from 0 to 100 in increments of 5, starting with a jump from 0 to 35. A kink is shown on the vertical axis close to origin. A dot is plotted at 0.5 on the horizontal axis and 45 on the vertical axis. A loosely packed cluster of data plots is plotted between 1 to 4.5 on the horizontal axis and 77 and 98 on the vertical axis.
A math teacher gave a math test. Interpret the scatterplot to determine which point is the outlier.
A. (1, 78)
B. (0.5, 45)
C. (4.5, 97)
D. (2.5, 87)

Answer 1

B. (0.5, 45)

All other points lie in a cluster around 1–4.5 hours and grades about 77–98; the point at (0.5, 45) is far below that cluster and does not follow the pattern, so it is the outlier.