Assignment:
Frequency Distributions and their Graphs
1. The Young Republicans Club asked its members how many hours they had worked during the previous week in part-time jobs. The following data lists the number of hours spent working during the previous week.
6 6 6 4 6 6 9 8 7 3 7 8
6 7 6 7 7 6 6 8 6 7 8 4
a. From these data complete the frequency table below. Round the relative frequencies to three decimal places.
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Hours
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Tally
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Frequency
f
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Midpoint
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Relative Frequency
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3 - 4
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5 - 6
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7 - 8
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9 - 10
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b. Using Excel construct a frequency histogram for the frequency table in part a.
c. Using Excel construct a relative frequency histogram for the frequency table in part a. Use the midpoint as the horizontal axis and frequency [f] as the vertical axis.
More Graphs and Displays
2. A research team studied the ages of patients who had heart attacks caused by smoking. The ages of 34 patients who suffered a heart attack are reported below.
29 30 36 41 45 50 57 61 28 50 66 58
60 38 36 47 40 32 58 46 61 40 55 32
61 56 45 46 62 66 38 40 40 27
Construct a Stem-and-Leaf Plot from these data with Key: 5 | 7 = 57.
3. A new DVD movie was rated by 900 reviewers. The follow data summarizes those ratings.
Complete the table for Relative Frequency. Using Excel, construct a pie chart using the relative frequency as the percent for each category. Round the relative frequencies to 3 decimal places. The wedges should be labeled with a descriptive label and a numeric label. Copy the graph from Excel into the project Word document.
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Rating
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Frequency
|
Relative Frequency
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Excellent
|
200
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|
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Good
|
360
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Fair
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290
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Poor
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50
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Measures of Central Tendency
4. The Young Republicans Club asked its members how many hours they had worked during the previous week in part-time jobs. The following data lists the number of hours spent working during the previous week.
6 6 6 4 6 6 9 8 7 3 7 8
6 7 6 7 7 6 6 8 6 7 8 4
a. Calculate the mean for these data. (Round to 2 decimal places)
b. Determine the median for these data.
Measures of Variation
5. IQ scores for seniors age 60 - 80 have a bell-shaped distribution with a mean of 100 and a standard deviation of 25. Use the Empirical Rule to find the percentage of seniors age 60 - 80 with IQ scores between 75 and 125.