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Lottery In Florida鈥檚 Play 4 lottery game, four digits between 0 and 9 inclusive are randomly selected each day. We normally expect that each of the 10 different digits will occur about 1/10 of the time, and an analysis of last year鈥檚 results shows that this did happen. Because the results are what we normally expect, is it correct to say that the distribution of selected digits is a normal distribution?

Stemplots. In Exercises 7 and 8, construct the stem plot.

Diastolic Blood Pressure Refer to the data listed in Exercise 6. Identify the two values that are closest to the middle when the data are sorted in order from lowest to highest. (These values are often used to find the median, which is defined in Section 3-1.)

Scatterplot. In Exercises 5鈥�8, use the sample data to construct a scatterplot. Use the first variable for the x-axis. Based on the scatterplot, what do you conclude about a linear correlation?

Heights of Fathers and Sons The table lists heights (in.) of fathers and the heights (in.) of their first sons (from Francis Galton).

Linear Correlation Coefficient In Exercises 9鈥�12, the linear correlation coefficient r is provided. Use Table 2-11 on page 71 to find the critical values of r. Based on a comparison of the linear correlation coefficient r and the critical values, what do you conclude about a linear correlation?

Using the data from Exercise 5 鈥淏rain Volume and IQ,鈥� the linear correlation coefficient is r = 0.127.

Seatbelts The Beams Seatbelts company manufactures鈥攚ell, you know. When a sample of seatbelts is tested for breaking point (measured in kilograms), the sample data are explored. Identify the important characteristic of data that is missing from this list: center, distribution, outliers, changing characteristics over time.

Normal Distributions. In Exercises 9 and 10, using a loose interpretation of the criteria for determining whether a frequency distribution is approximately a normal distribution, determine whether the given frequency distribution is approximately a normal distribution. Give a brief explanation.

Best Actresses Refer to the frequency distribution from Exercise 5

Time-Series Graphs. In Exercises 9 and 10, construct the time-series graph.

Gender Pay Gap Listed below are women鈥檚 median earnings as a percentage of men鈥檚 median earnings for recent years beginning with 1990. Is there a trend? How does it appear to affect women?

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