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The box-and-whisker plots below show the ages of the players on the New York Yankees and the Texas Rangers baseball teams during the 2002 season.

1. Compare the median, range, and interquartile range for the two teams.
2. About what percent of the Yankees are less than 31 years old? About what percent of the Rangers are less than 31 years old?

Which team would you say is the 鈥渙lder鈥� team? Explain.

The histogram shows the average number of vacation days that working citizen in 30 major cities in Europe and North America have each year.

1. What Interval has the greatest frequency?
2. In what percent of the cities surveyed do working citizens have fewer than 20 vacation days per year?
3. Citizens of Shanghai, China, average 16 vacation days per year. How does Shanghai compare with the data given for North America and Europe? Explain.

The stem-and-leaf plot shows the times (in minutes) for 30 men who completed the 2002 Boston Marathon using a wheelchair.

$\begin{array}{l}\begin{array}{ccccccccccccc}8& 3& 6& & & & & & & & & & \\ 9& 0& 3& 3& 5& 6& & & & & & & \\ 10& 0& 0& 1& 3& 3& 3& 3& 3& 3& 3& 6& 9\\ 11& 1& 2& 3& 9& 9& & & & & & & \\ 12& 1& 2& 4& 9& 9& & & & & & & \\ 13& 3& & & & & & & & & & & \end{array}\\ \\ \text{Key:8|3}=8\text{3minutes}\end{array}$

1. What was the fastest time?
2. Find the median of the times.
3. What percent of the participants finished the race in less than 2 hours?

The circle graph shows the results of a survey that asked students what their favourite beach activity is. In what way is this graph misleading? Explain.

Give an example of a non-random sampling method.

Compare stem-and-leaf plots and histograms. How are they alike? What advantages do stem-and-leaf plots have over histograms? What advantages do histograms have over stem-and-leaf plots?

You buy a sweater that is on sale for 15% off the original price of $40. What is the sale price of the sweater?

You ask the first 30 people coming out of a movie theatre what type of movie they prefer. Is your sample likely to represent the population of all moviegoers? Explain.