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Ex5. A random sample of 64 observations has a mean 36 and standard deviation
S = 5. Test the null hypothesis µ ≥ 40 against the alternative µ < 40 using a 0.05 level of significance.
Ex6. A random sample of 160 observations from a normal population the sample mean 15 and the sample variance s2 = 250 .The test hypothesis Ho µ ≤ 149 against the alternative µ > 149 at α = 0.05

Example 7: A researcher claims that the average wind speed in a certain city is 8 miles per hour. A sample of 32 days has an average wind speed of 8.2 miles per hour. The standard deviation of the sample is 0.6 mile per hour. At α = 0.05, is there enough evidence to reject the claim?
Page389
Q19. A manufacturer states that the average life time of its television sets is more than 24 months. The standard deviation of the population is 10 months. One hundred sets are randomly selected and tested. The average lifetime of the sample is 85.1 months. Test the claim that the average life time of the sets is more than 84 months. At α = 0.01, is there enough evidence to reject the claim?
T test
Pag394
Ex12: A job placement director claims that the average starting salary for nurses is $24,000 A sample of 10 nurses has a mean of $23,450 and a standard deviation of $400 is there enough evidence to reject the director claim at α = 0.05?

Page 398
Q7: The average salary of graduates entering the actuarial field is reported to be $40,000. To test this, a Statistics professor surveys 20 graduates and finds their average salary to be $43228 with a standard deviation (s) of $4,000. Using α = 0.05 has he shown the reported salary

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