In Exercise 35 of Homework 3.3, you analyzed the ages of 1098 people (on foot or in a vehicle) stopped by police in New York City on December 1, 2012. Without being able to view the police reports or interview the police officers, the author did his best to clean up the data. The ages (in years) of the remaining 1089 people are described by the relative frequency histogram in Fig. 89. Some of the ages are less than 10 years or greater than 65 years, but the bars for those ages would not be visible.

a. Describe the shape of the distribution. What does it mean in this situation?
b. Estimate the proportion of people stopped by police who were at most 19 years of age.
c. From inspecting the histogram, a student says that the result you found in part (b) is the correct proportion for any day. What would you tell the student?
d. Identify which class contains the 50th percentile, which is a measure of the center. Are the observations in the class typical values? Explain.

Ages of People Stopped by Police 0.29 0.3 0.27 0.2 0.14 0.09 0.05 0.04 0.04 0.02 0.02 0.01 0.02 10 15 20 25 30 35 40 45 50 55 60 65 Ages (years)