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Question
The U.S. Census Bureau (Annual Social & Economic Supplement) collects demographics concerning the number of people in families per household. Assume the distribution of the number of people per household is shown in the following table:| x | P(x) |
| 2 | 0.27 |
| 3 | 0.25 |
| 4 | 0.28 |
| 5 | 0.13 |
| 6 | 0.04 |
| 7 | 0.03 |
Compute the variance and standard deviation of the number of people in families per household.
A) Variance=1.6499, standard deviation=1.2845
B) Variance=1.2845, standard deviation=1.6499
C) Variance=6.7182, standard deviation=2.5919
D) Variance=2.5919, standard deviation=6.7182
Answer
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A) Because t = -2.69 is less than -2.3456, do not reject H0
Conclude that 2012 average out-of-pocket prescription drug expenses are not lower than the 2002 average.
B) Because t = -2.69 is less than -2.3456, reject H0
Conclude that 2012 average out-of-pocket prescription drug expenses are lower than the 2002 average.
C) Because t = -1.69 is less than -0.8712, reject H0
Conclude that 2012 average out-of-pocket prescription drug expenses are lower than the 2002 average.
D) Because t = -1.69 is less than -0.8712, do not reject H0
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A) p-value = 0.0872 > 0.025; therefore do not reject H0
B) p-value = 0.0422 > 0.005; therefore do not reject H0
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