Exam 10: One-Sample Tests of Hypothesis

It is claimed that in a bushel of peaches less than ten percent are defective.A sample of 400 peaches is examined and 50 are found to be defective.What is the null hypothesis?

What are the critical z-values for a two-tailed hypothesis test if $\alpha$ = 0.01?

The mean weight of newborn infants at a community hospital is 6.6 pounds.A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0,7.3,6.0,8.8,6.8,8.4,and 6.6 pounds.What is the sample mean?

As sample sizes decrease,rejecting the null hypotheses is less likely.

The mean gross annual incomes of certified welders are normally distributed with the mean of $20,000 and a standard deviation of $2,000.The ship building association wishes to find out whether their welders earn more or less than $20,000 annually.The alternate hypothesis is that the mean is not $20,000.If the level of significance is 0.10,what is the critical value?

A p-value is a probability.

Based on the Nielsen ratings,the local CBS affiliate claims its 11:00 PM newscast reaches 41% of the viewing audience in the area.In a survey of 100 viewers,36% indicated that they watch the late evening news on this local CBS station.What is the null hypothesis?

A manufacturer claims that less than 1% of all his products do not meet the minimum government standards.A survey of 500 products revealed ten did not meet the standard.What is the alternate hypothesis? ____________________

To prevent bias,the level of significance is selected before setting up the decision rule and sampling the population.

If we do not reject the null hypothesis based on sample evidence,we have proven beyond doubt that the null hypothesis is true.

A null hypothesis makes a claim about a

The mean weight of newborn infants at a community hospital is 6.6 pounds.A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0,7.3,6.0,8.8,6.8,8.4,and 6.6 pounds.What is the sample variance?

A Type I error is the probability of rejecting a true null hypothesis.

A sample proportion is found by dividing the number of successes in the sample by the number sampled.

The average cost of tuition,room and board at small private liberal arts colleges is reported to be $8,500 per term,but a financial administrator believes that the average cost is higher.A study conducted using 350 small liberal arts colleges showed that the average cost per term is $8,745 with a standard deviation of $1,200.Let = 0.05.What is the p-value for this test?

As sample sizes decrease,the variability of sample means increases.

What are the two critical values for a two-tailed test with a 0.01 level of significance when n is large and the population standard deviation is known?

A manufacturer claims that less than 1% of all his products do not meet the minimum government standards.A survey of 500 products revealed ten did not meet the standard.What is the z-statistic? _______________

What is the level of significance?

A manufacturer wants to increase the absorption capacity of a sponge.Based on past data,the average sponge could absorb 3.5 ounces.After the redesign,the absorption amounts of a sample of sponges were (in ounces): 4.1,3.7,3.3,3.5,3.8,3.9,3.6,3.8,4.0,and 3.9.What is the decision rule at the 0.01 level of significance to test if the new design increased the absorption amount of the sponge?