7 Steps for Tests of Significance1. State the research question.2. Identify the parameter.3. State the hypotheses.4. Choose the method.5. Do the test.6. Interpret the p-value and alpha. Must be stated in the context of the problem.7. Draw a conclusion. Must be stated in the context of the problem.

ilings Review View ? Tell me v AaBbCcDdE AaBbCcDdE AaBbCcD AaBbCcDdE A Normal No Spacing Heading 1 Heading 2 E Styles Paragraph 7 lests of Significance on Proportions and Means 1. A fitness magazine advertises that the average monthly cost of joining a health club is $25. A consumer advocacy group decides to test this claim. They randomly sample 18 clubs and find a mean monthly cost of $26.25 and a standard deviation of $3.23. Assume the underlying distribution is normal. At the 10% significance level, do they have enough evidence to reject the advertiser's claim? 2. In 36 randomly selected seawater samples, the mean sodium chloride concentration was 23 cc/cubic meter and the standard deviation was 6.7 cc/cubic meter. If a previous collection of samples found a mean sodium chloride concentration of 24 cc/cubic meter, has there been a change in the concentration at the 10% significance level? 3. An Air Force base mess hall has received a shipment of 10,000 gallon-size cans of cherries. The supplier claims that the average amount of liquid is 0.25 gallon per can. A government inspector took a random sample of 100 cans and found the average liquid content to be 0.28 gallon per can with a standard deviation of 0.10. Does this indicate that the supplier's claim is too low? (Use a 5% significance level.) 4. A researcher claims that less than 30% of adults in the United States are allergic to trees, weeds, flowers, and grasses. In a random sample of 86 adults, 20% say they have such an allergy. At a 5% significance level, is there enough evidence to support the researcher's claim? 5. The following data set presents the time in minutes for a random sample of phone calls conducted by customer service employees at Psst, Inc. In the past the company has found that the average call time for customer service is 6 minutes. 7.5 2.0 12.1 8.8 9.4 7.3 1.9 2.8 7.0 7.3 At the 5% significance level, do these data indicate that the average call time increased? Assume an underlying normal distribution. 6. Let x be a random variable representing the percentage of protein content for early bloom alfalfa hay. The average percentage protein content of such early bloom alfalfa should be 17.2%. A Colorado rancher is thinking of buying baled hay but suspects that the hay is from a later summer cutting with lower protein content. A small amount of hay was removed from each bale of a random sample of 50 bales. The average protein content - from the samples was 15.8% with sample standard deviation 5.3%. Use a 5% significance level to test the claim that this hay has lower average protein content than early bloom alfalfa. 7. A survey found that more than 38% of U.S. adults regularly watch a cable news broadcast. You decide to test this claim and ask a random sample of 75 adults whether they regularly watch a cable news broadcast. Of the 75 adults, 33 respond yes. Is there enough evidence to support the claim at the 1% significance level