3.10 Bivariate descriptive statistics: homework  (Page 5/12)

Javier and Ercilia are supervisors at a shopping mall. Each was given the task of estimating the mean distance that shoppers live from the mall. They each randomly surveyed 100 shoppers. The samples yielded the following information:

• a How can you determine which survey was correct?
• b Explain what the difference in the results of the surveys implies about the data.
• c If the two histograms depict the distribution of values for each supervisor, which one depicts Ercilia's sample? How do you know?

  

• d If the two box plots depict the distribution of values for each supervisor, which one depicts Ercilia’s sample? How do you know?

  

Below are the 2010 obesity rates by U.S. states and Washington, DC. ( Source: http://www.cdc.gov/obesity/data/adult.html) )

• a. Construct a bar graph of obesity rates of your state and the four states closest to your state. Hint: Label the x-axis with the states.
• b. Use a random number generator to randomly pick 8 states. Construct a bar graph of the obesity rates of those 8 states.
• c. Construct a bar graph for all the states beginning with the letter "A."
• d. Construct a bar graph for all the states beginning with the letter "M."

A music school has budgeted to purchase 3 musical instruments. They plan to purchase a piano costing $3000, a guitar costing $550, and a drum set costing $600. The mean cost for a piano is $4,000 with a standard deviation of $2,500. The mean cost for a guitar is $500 with a standard deviation of $200. The mean cost for drums is $700 with a standard deviation of $100. Which cost is the lowest, when compared to other instruments of the same type? Which cost is the highest when compared to other instruments of the same type. Justify your answer numerically.