A cell phone manufacturer claims that the batteries in its latest model provide 20 hours of...

A cell phone manufacturer claims that the batteries in its latest model provide 20 hours of continuous use. In order to verify this claim, and independent testing firm checks the battery life of 100 phones. They find that the batteries in these 100 phones last an average of 19 hours with a standard deviation of 5 hours. Conduct an appropriate hypothesis test to check whether the results from this sample provide sufficient evidence that the true mean battery life is significantly less than 20 hours.

Is this a question about the sample mean or the sample proportion? Explain how you know.

What is the most appropriate test, a two-tailed test, a right-tailed test, or a left-tailed test? Explain how you know.

State the null and alternative hypotheses. Make sure to use proper notation.

Calculate the test statistic. Make sure to show all your computations.

Determine the P-value. Make sure to explain how you obtained the value.

f. State the decision about the null hypothesis as well as the conclusion from your hypothesis test in the context of the problem.

Expert Solution

milcah answered 11 months ago

A cell phone manufacturer claims that the population mean battery life of its flagship smartphone model,...

A cell phone manufacturer claims that the population mean battery life of its flagship smartphone model, the Black Bear, is greater than the population mean battery life of the largest competitor, the Grizzly. A consumer advocacy publication tests this claim by purchasing a random sample of Black Bear smartphones and a random sample of Grizzly smartphones. Members of the publication charged each smartphone to full capacity and then had the smartphones play back the same videos until the batteries were...

A manufacturer claims that the mean lifetime of its lithium batteries is 1400 hours. A homeowner...

A manufacturer claims that the mean lifetime of its lithium batteries is 1400 hours. A homeowner selects 30 of these batteries and finds the mean lifetime to be 1380 hours with a standard deviation of 80 hours. Test the manufacturer's claim using a two-tailed test. Use α = 0.05. Round to 3 decimal places. 1.) State the Null and Alternative Hypotheses (mathematically, not in words). 2.) Specify the critical t values for the rejection region (that is, find the critical...

A manufacturer claims that the mean lifetime of its lithium batteries is 1500 hours. A home...

A manufacturer claims that the mean lifetime of its lithium batteries is 1500 hours. A home owner selects 30 of these batteries and finds the mean lifetime to be 1470 hours with a standard deviation of 80 hours. Test the manufacturer's claim. Use a=0.05 . Round the test statistic to the nearest thousandth. a) Hypothesis : b) Critical value (tcritical) : c) Test statistic (tstat) and the decision about the test statistic: (reject or fail to reject Ho) : d)...

1. A manufacturer claims that the mean lifetime of its lithium batteries is 1200 hours. A...

1. A manufacturer claims that the mean lifetime of its lithium batteries is 1200 hours. A homeowner selects 26 of these batteries and finds the mean lifetime to be 1100 hours with a standard deviation of 85 hours. Test the manufacturer's claim. Use α = 0.05. Round the test statistic to the nearest thousandth. Please solve using excel

A manufacturer claims that the mean lifetime of its lithium batteries is 1100 hours buta group...

A manufacturer claims that the mean lifetime of its lithium batteries is 1100 hours buta group of homeowners believe their battery-life is different than this manufactureds claim. A homeowner selects 35 of these batteries and finds the mean lifetime to be 1080 hours with a standard deviation of 80 hours. Test the manufacturer's claim. Use u = 0.10 and the p-value approach. Round the test statistic to the nearest thousandth. Every solution should have the following 8 steps clearly written...

A company claims their new cell phone model has a mean battery life of 60 hours....

A company claims their new cell phone model has a mean battery life of 60 hours. A consumer group suspects this claim is exaggerated so they record the battery life of 100 randomly selected cell phones of this model and conduct a hypothesis test. The sample gives a mean life of 58 hours and a standard deviation of 10. Use this information to answer the following questions. a. What is the null hypothesis about the population mean battery life? b....

Question 1: A mobile phone manufacturer claims that the batteries in the manufactured mobile phones are...

Question 1: A mobile phone manufacturer claims that the batteries in the manufactured mobile phones are used for an average of 140 hours after being charged once. For this purpose, 17 telephone batteries were chosen randomly and it was determined that they could be used for an average of 136 hours and the standard deviation was 29 hours. According to this; a-) Is the batteries lasting less than 140 minutes according to 1% significance level? Examine statistically. b-) Determine the...

A manufacturer of automobile batteries claims that the distribution of the lengths of life of its...

A manufacturer of automobile batteries claims that the distribution of the lengths of life of its battery has mean of 54 months and a standard deviation of 6 months. Recently manufacturer has received a rash of complaints from unsatisfied customers whose batteries have died earlier than expected. Suppose a consumer group decides to check the manufacturer’s claim by purchasing a sample of 50 of these batteries and subjecting them to test that determine battery life. Assuming that the manufacturer claim...

A manufacturer of car batteries claims that the life of the company’s batteries in years is...

A manufacturer of car batteries claims that the life of the company’s batteries in years is approximately normally distributed with a population variance of 0.81. A random sample of 10 of these batteries has a variance of 1.44. Construct a 95% C.I. for . Use and to construct the interval.

A manufacturer of computers claims its newest model has a mean battery life of 10 hours,...

A manufacturer of computers claims its newest model has a mean battery life of 10 hours, although normally distributed variations in computer production will cause some units to have more or less battery life. A consumer advocacy group is concerned the true mean is less and is constructing a hypothesis test at the 95% significance level to evaluate the claim. In their testing for battery life, a sample of 25 randomly selected units gave a sample mean of ̄x25 =...

Question