Exam 3: Displaying and Summarizing Quantitative Data

During student-teacher negotiations at a certain high school,teachers seek to change the number of times students are allowed to be tardy,saying that the semester "average" is 8 days of tardiness per student.The students counter that the "average" student is only tardy 4 times per semester.Explain how both sides may be correct,identifying the measure of centre you think each side is using and why the difference might exist.

Here are the weights,in grams,of several snack crackers.

The histogram shows the cost of living,in dollars,in 32 Canadian towns.

The local Tupperware dealers earned the following commissions,in dollars,last month. Round your answer to the nearest cent.

The test scores of 15 students are listed below.Find the lower quartile (Q1)by hand.

A small company employs a supervisor at $1,300 a week,an inventory manager at $800 a week,7 stock boys at $400 a week,and 5 drivers at $700 a week.Which measure of centre best describes a typical wage at this company,the mean at $600 or the median at $550?

The test scores of 19 students are listed below.Find the interquartile range (IQR)by hand.

In a survey,20 people were asked how many magazines they had purchased during the previous year.The results are shown below.Construct a histogram to represent the data.Use 4 bins with a bin width of 10,and begin with a lower bin limit of -0.5.What is the approximate amount at the centre?

The data below give the number of tornadoes that happened each year in a certain county from 1948 through 2004.Create a dotplot of these data.

The weights,in kilograms,of the members of the varsity football team are listed below.Create a stem-and-leaf display of the data.Use split stems by separating each stem into 5 stems.

Here are the commutes (in kilometres)for a group of six employees.Find the standard deviation.

Ages of high school students.

Shown below are the histogram and summary statistics for the reading scores of 29 fifth graders. Which measures of centre and spread would you use for this distribution?

Here are the amounts,in dollars,spent by six students at a university book store. Round your answer to the nearest cent.

The histograms display the body fat percentages of 42 female students and 48 male students taking a college health course.For which of the variables depicted in the histograms would you be most satisfied to summarize the centre with a mean? Explain.

Here are the number of baseball games that Dave attended over the last several seasons. 1 15 17 21 30 30 49

Here are costs (in dollars)of 12 refrigerators.Find the range.

In a survey,26 voters were asked their ages.The results are shown below.Construct a histogram to represent the data (with 5 bins beginning with a lower bin limit of 19.5 and a bin width of 10).What is the approximate age at the centre?

Here are the average mathematics achievement scores for ninth graders in 32 counties.Find the standard deviation.

The weekly salaries,in dollars,of 16 government workers are listed below.Find the lower quartile (Q1)by hand.