Hypothesis testing for one sample mean.
Faced with rising fax costs, a firm issued a guideline that transmissions of 10 pages or more must be sent by 2-day mail instead. Exceptions are allowed, other than they want the average to be 10 or below. The firm examined 35 arbitrarily chosen fax transmissions during the next year, yielding a sample mean of 14.44 with a standard deviation of 4.45 pages.
(a) At.01 level of significance, is the true mean greater than 10?
(b) Use Excel to find the right-tail p-value.
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Hypotheses
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H0: _ = 10 vs. _ > 10
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Level of Significance:
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0.01
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Decision Rule
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Reject the null hypothesis if p-value < 0.01
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Calculation:
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Hypothesis Test: Mean vs. Hypothesized Value
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Hypothesized value
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10.000
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Mean Sample
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14.400
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Std. dev.
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0.752
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n
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35
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5.85
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Z
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2.46E
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P-value
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