1. A sample of 9 highschool seniors in a school systemreports a mean of 5 hours
ID: 2951488 • Letter: 1
Question
1. A sample of 9 highschool seniors in a school systemreports a mean of 5 hours worked at a part time jobs during arecent week. The sample standard deviation was 3 hrs. Do these dataprovide sufficient evidence to indicate that the mean for thepopulation is less than 8 hours? Assume a normally distributedpopulation.2. The owner of Shopping center claims that more than 50% ofhouseholds near there have at least 1 member who shops at thecenter at least once a week. In a sample of 300 households withinthe area, they found that members of 171 households did so. Dothese data provide sufficient evidence to support the shoppingcenter owner's claim? Let = 0.01.
3. A random sample of 16 college freshmen who plan to major inmarketing and a random sample of 13 who plan to major in accountingare given a sales aptitude test. The variance of the scores of themarketing majors is 7.29. The variance of the scores of theaccounting majors is 39,69. Do these data provide sufficientevidence to indicate , at the 0.05 level of significance, that the2 population variances are different? state all necessaryassumption.
4. O' Cinnor drugs, a pharmaceuticals manufacturer, is concernedwith the side effects of a depressant drug when used by normalaldults. A researcher would like to find a dosage that wouldprodure sedation but not be strong enough to cause serious sideeffects. A random sample of 16 subjects taking part in theexperiment with the drug achived sedation with the followingdosage, in milligrams per kilogram of body weight: 1.6, 1.8, 7.3,5.7, 3/0, 1.6, 3.8, 3.1, 7.8, 7.4, 4.2, 1.6, 2.1, 2.1, 5.5, 4.4
Do these data provide sufficient evidence to indicate that the meandosage required to produce sedation is greater than 2.5 milligramper kilogram of body weight? let =0.05
5. Anofficial with bartram paint and varnish, Inc. belives thatmore than one-third of ordered raw material are not delivered ontime. She compares the actual delivery date with the promiseddelivery date on a rendom sample of 100 orders and finds that 38orders were not delivered on time. Do these data support ferbelief? let =0.01
Explanation / Answer
As you mentioned in the first problem that Sample size n= 9 Sample mean = x-bar = 5 and sample standard deviation = s =3 Null Hypothesis: The data does not provide sufficientevidence to indicate that the mean for the population is less than8 hours. Alternative Hypothesis: The data provide sufficient evidence toindicate that the mean for the population is less than 8 hours We have to do one sample t-test for this type of situation The formula for the test statistic is t= (X-bar - )/s/n = (5-8)/3/9 = -3 The P-value: 0.017 Since the p-value is less than 0.05, the level of significance sowe reject the null hypothesis and conclude that the data providesufficient evidence to indicate that the mean for the population isless than 8 hours
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.