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A random sample of n1 = 16 communities in western Kansas gave the following information for people under 25 years of age.
100 | 92 | 121 | 129 | 93 | 123 | 112 | 93 |
125 | 95 | 125 | 117 | 97 | 122 | 127 | 88 |
A random sample of n2 = 14 regions in western Kansas gave the following information for people over 50 years old.
93 | 108 | 103 | 98 | 112 | 88 | 110 |
79 | 115 | 100 | 89 | 114 | 85 | 96 |
(i) Use a calculator to calculate x1, s1, x2, and s2. (Round your answers to four decimal places.)
x1 | = |
s1 | = |
x2 | = |
s2 | = |
What is the value of the sample test statistic? (Test the difference μ1 − μ2. Round your answer to three decimal places.)
A random sample of n1 = 16 communities in western Kansas gave the following information for people under 25 years of age.
100 | 92 | 121 | 129 | 93 | 123 | 112 | 93 |
125 | 95 | 125 | 117 | 97 | 122 | 127 | 88 |
A random sample of n2 = 14 regions in western Kansas gave the following information for people over 50 years old.
93 | 108 | 103 | 98 | 112 | 88 | 110 |
79 | 115 | 100 | 89 | 114 | 85 | 96 |
(c) Find (or estimate) the P-value.
(d) Based on your answers in parts (a) to (c), will you reject or fail to reject the null hypothesis? Are the data statistically significant at level α?
(e) Interpret your conclusion in the context of the application.
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