MATLAB: An Introduction with Applications
6th Edition
ISBN: 9781119256830
Author: Amos Gilat
Publisher: John Wiley & Sons Inc
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An LED light bulb manufacturer claims that the average lifespan of its 60-watt LED light bulbs is 43,000 hours.
A corporate watchdog group is suspicious of the company's claim and thinks that the true average lifespan of the 60-watt LED light bulbs produced by the company may be less than the advertised 43,000 hours. The group collected and tested a random sample of 240 light bulbs and found the average lifespan of the sample was 42,958 hours.
Use the p-value method to test the hypothesis that themean lifespan of this brand of 60-watt LED light bulb is less than 43,000 hours, using α=0.025α=0.025. Assume the standard deviation of the lifespan of all such light bulbs is known to be 430 hours.
State the null and alternative hypothesis for this test.
H0:H0:
H1:H1:
Determine if this test is left-tailed, right-tailed, or two-tailed.
Should the standard normal (zz) distribution or Student's (tt) distribution be used for this test?
Determine the test statistic for the hypothesis test. Round the solution to two decimal places.
Determine the p-value for the hypothesis test. Round the solution to four decimal places.
Determine the appropriate conclusion for this hypothesis test.
A corporate watchdog group is suspicious of the company's claim and thinks that the true average lifespan of the 60-watt LED light bulbs produced by the company may be less than the advertised 43,000 hours. The group collected and tested a random sample of 240 light bulbs and found the average lifespan of the sample was 42,958 hours.
Use the p-value method to test the hypothesis that the
State the null and alternative hypothesis for this test.
H0:H0:
H1:H1:
Determine if this test is left-tailed, right-tailed, or two-tailed.
- right-tailed
- two-tailed
- left-tailed
- The standard normal (zz) distribution should be used
- The Student's tt distribution should be used
Determine the p-value for the hypothesis test. Round the solution to four decimal places.
Determine the appropriate conclusion for this hypothesis test.
- The sample data do not provide sufficient evidence to reject the alternative hypothesis that the mean lifespan of the 60-watt LED light bulbs produced by this company is less than 43,000 hours and thus we conclude that the company's claim that the light bulbs last an average of 43,000 hours is likely false.
- The sample data provide sufficient evidence to reject the null hypothesis that the mean lifespan of the 60-watt LED light bulbs produced by this company is 43,000 hours and thus we conclude that the company's claim that that the average lifespan of the 60-watt LED light bulbs is 43,000 hours is likely false.
- The sample data do not provide sufficient evidence to reject the null hypothesis that the mean lifespan of the 60-watt LED light bulbs produced by this company is 43,000 hours and thus we conclude that the company's claim that that the average lifespan of the 60-watt LED light bulbs is 43,000 hours is likely true.
- The sample data provide sufficient evidence to reject the alternative hypothesis that the mean lifespan of the 60-watt LED light bulbs produced by this company is less than 43,000 hours and thus we conclude that the company's claim that the light bulbs last an average of 43,000 hours is likely true.
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