Assignment:
Assume that both samples are independent simple random samples from populations having normal distributions.
Radiation in Baby Teeth Listed below are amounts of strontium-90 (in millibecquerels or mBq per gram of calcium) in a simple random sample of baby teeth obtained from Pennsylvania residents and New York residents born after 1979 (based on data from "An Unexpected Rise in Strontium-90 in U.S. Deciduous Teeth in the 1990s," by Mangano, et al., Science of the Total Environment). Use a 0.05 significance level to test the claim that amounts of Strontium-90 from Pennsylvania residents vary more than amounts from New York residents.
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Pennsylvania:
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155
|
142
|
149
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130
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151
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163
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151
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142
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156
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133
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138
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161
|
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New York:
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133
|
140
|
142
|
131
|
134
|
129
|
128
|
140
|
140
|
140
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137
|
143
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Assume that both samples are independent simple random samples from populations having normal distributions.
BMI for Miss America Listed below are body mass indexes (BMI) for Miss America winners from two different time periods. Use a 0.05 significance level to test the claim that winners from both time periods have BMI values with the same amount of variation.
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BMI (from recent winners):
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19.5
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20.3
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19.6
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20.2
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17.8
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17.9
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19.1
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18.8
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17.6
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16.8
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BMI (from the 1920s and 1930s):
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20.4
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21.9
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22.1
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22.3
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20.3
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18.8
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18.9
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19.4
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18.4
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19.1
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