Question 451336
Set up the null and alternate hypotheses for the situations where the analyst is trying to prove 
a. The average income of men is greater than that of the average income of women 
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Ho: u(men)-u(women)<= 0
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b. The average age of the workforce is greater than 30 years
Ho: u <= 30
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c. A new car model will get greater average gas mileage than the old model.
Ho: u(new)-u(old) <= 0

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The main criteria for Ho is that it must contain equality.
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Cheers,
Stan H.
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