Question 483926
State the null hypothesis Ho and the alternative hypothesis Ha that would be used for a hypothesis test related to each of the following statements: 
o a. The mean age of the students enrolled in evening classes at a certain college is greater than 26 years.
Ho: u <=26
Ha: u > 26
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o b. The mean weight of packages shipped on Air Express during the past month was less than 36.7 lb.
Ho: u >= 36.7
Ha: u < 36.7
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o c. The mean life of fluorescent light bulbs is at least 1600 hours.
Ho: u >= 1600
Ha: u < 1600
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o d. The mean strength of welds by a new process is different from 570 Ib per unit area, the mean strength of welds by the old process.
Ho: u = 570
Ha: u is to equal to 570
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The Key idea in setting up Ho and Ha:
The equal sign must ALWAYS appear in Ho.
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Cheers,
Stan H.
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