A manufacturer claims that the mean lifetime of its fluorescent bulbs is 1300 hours. A homeowner...

A manufacturer claims that the mean lifetime of its fluorescent bulbs is 1300 hours. A homeowner selects 25 bulbs and finds the mean lifetime to be 1270 hours with a standard deviation of 80 hours. Test the manufacturer's claim. Use α = 0.05.

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orchestra answered 2 years ago

A manufacturer claims that the mean lifetime of its fluorescent bulbs is 1000 hours. The lifetimes...

A manufacturer claims that the mean lifetime of its fluorescent bulbs is 1000 hours. The lifetimes are normally distributed with a standard deviation of σ = 80 hours. A homeowner decides to test the manufacturer's claim; in a random sample of 40 bulbs, the mean lifetime is 980 hours. At a significance level of α = 0.05, does this data provide evidence to reject the manufacturer's claim? Show all 7 steps for p-value method.

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

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A manufacturer claims that the mean lifetime, u, of its light bulbs is 50 months. The...

A manufacturer claims that the mean lifetime, u, of its light bulbs is 50 months. The standard deviation of these lifetimes is 8 months. Fifty bulbs are selected at random, and their mean lifetime is found to be 49 months. Can we conclude, at the 0.1 level of significance, that the mean lifetime of light bulbs made by this manufacturer differs from 50 months?

A manufacturer of light bulbs claims that the average lifetime of one of their bulbs is...

A manufacturer of light bulbs claims that the average lifetime of one of their bulbs is more than 900 hours. A consumer advocacy group wants to test this claim. They obtained a simple random sample of 61 bulbs and timed how long they took to burn out. They obtained a sample mean of 907.5 hours with a standard deviation of 16.5 hours. It’s your job to test the claim at the 5% significance level and determine if the manufacturer is...

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

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

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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...

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BIG Corporation advertises that its light bulbs have a mean lifetime, u , of 3000 hours....

BIG Corporation advertises that its light bulbs have a mean lifetime, u , of 3000 hours. Suppose that we have reason to doubt this claim and decide to do a statistical test of the claim. We choose a random sample of light bulbs manufactured by BIG and find that the mean lifetime for this sample is 2860 hours and that the sample standard deviation of the lifetimes is hours. Based on this information, answer the questions below. What are the...

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