Following is a list of number of hazardous waste sites in each of 50 states of United States as of April 1995. The data are taken from The World Almanac and Book of Facts 1996 (World Almanac Books, Mahwah, NJ, 1996). The list has been sorted in numerical order.
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1
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2
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3
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4
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4
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5
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6
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8
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8
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9
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10
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10
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10
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11
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11
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11
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12
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12
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12
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12
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13
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13
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14
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15
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16
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17
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17
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18
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18
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19
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19
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20
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22
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23
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24
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25
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29
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30
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33
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37
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38
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39
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40
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55
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58
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77
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81
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96
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102
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107
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a) Make a stem and leaf plot of this data using leaf unit =1, with two leaf categories per stem. Also find the increment.
b) Determine the sample mean, sample standard deviation and sample median of the number of hazardous waste sites in each of the 50 states.
c) What proportion of hazardous waste sites is more than one standard deviation greater than the mean?
d) Construct a frequency table and display it as a histogram using a class width of 10. [Recall: LCB is included in the class interval whereas UCB is not included.] Your first class should be [0, 10).
e) What proportion of the 50 states has between 40 and 80 hazardous waste sites?(include 40 and 80)
f) How would you describe the shape of the histogram? (right skewed, left skewed, normal or inconclusive)
g) Find 3 quartiles (i.e. Q1, Q2 (median), Q3 ), and construct a boxplot for these data. Does the boxplot show any outliers? If so, state them.