Question

In: Statistics and Probability

a company manufactures light bulb. the company want the bulbs to have a mean life span...

a company manufactures light bulb. the company want the bulbs to have a mean life span of 99t hours. this average is maintained by periodically testing random sample of 25 light bulbs. if the t-value fail between -t0.90 and t0.90, then the company will be satisfied that it is manufacturing acceptable light bulbs. for a random sample, the mean life span of the sample is 1000 hours and the standard deviation is 25 hours. assume the life span are approximately normally distributed. is the company making acceptable light bulb. explain
the company ..... making acceptable light bulbs because the t-value for the sample is t = ....... and t0.90 = ......

Solutions

Expert Solution

ANSWER :

orchestra answered 1 year ago
Next > < Previous

Related Solutions

A manufacturer of light bulbs finds that one light bulb model has a mean life span...
A manufacturer of light bulbs finds that one light bulb model has a mean life span of 1025 h with a standard deviation of 80 h. What percent of these light bulbs will last as follows? (Round your answers to one decimal place.) (a) at least 970 h % (b) between 810 and 880 h %
A company manufactures light bulbs. These light bulbs have a length of life that is normally...
A company manufactures light bulbs. These light bulbs have a length of life that is normally distributed with a known standard deviation of 40 hours. If a sample of 36 light bulbs has an average life of 780 hours, find the 95 percent confidence interval for the population mean of all light bulbs manufactured by this company.
1. The mean life span of population of light bulbs manufactured by a particular company is...
1. The mean life span of population of light bulbs manufactured by a particular company is found to be 2400 hours with a standard deviation of 250 hours. A sample of 100 light bulbs produced in a lot is found to have a mean life span of 2300 hours. Test whether the population mean is less than sample mean. Assume α = 0.01.
Suppose the life span of a light bulb is normally distributed with mean 1000 hours and...
Suppose the life span of a light bulb is normally distributed with mean 1000 hours and standard deviation 75 hours. (a) Find the 57th percentile of this distribution. (b) Find the probability that a random light bulb will last longer than 1100 hours. (c) Find the probability that the life span of a light bulb will be more than 3.14 standard deviations away from the mean. (d) Suppose you take a sample of 15 light bulbs and measure the average...
The life span of 100 W light bulbs manufactured by a company are tested. It is...
The life span of 100 W light bulbs manufactured by a company are tested. It is found that (8 %) of the light bulbs are rejected. A random sample of 15 bulbs is taken from stock and tested. The random variable X is the number of bulbs that is rejected. a. Give four reasons why ? will have a binomial distribution. b. Use a formula to find the probability that 2 light bulbs in the sample are rejected. c. If...
GE, a company that makes light bulbs claims that its bulbs have a mean life of...
GE, a company that makes light bulbs claims that its bulbs have a mean life of 800 hours with a standard deviation of 32 hours. Show all work a)If you buy a four-pack of bulbs, what is the probability that the mean life will be 775 to 850 hours for that four-pack ? b)If you buy a case of 40 bulbs, what is the probability that the mean lifewill be 775 to 850 hours for the entire case? answers accurate...
A manufacturer of light bulbs claims that its light bulbs have a mean life of 1520...
A manufacturer of light bulbs claims that its light bulbs have a mean life of 1520 hours. If a random sample of 40 bulbs is tested and has an average life of 1500 hours and the standard deviation is 80 hours, is there sufficient evidence to claim that the mean life is different than the manufacturer's claim? Use alpha = 0.01. Calculate the test statistic. Calculate a confidence interval for the true mean light bulb life. Use the level of...
A light-bulb manufacturer advertises that the average life for its light bulbs is 900 hours. A...
A light-bulb manufacturer advertises that the average life for its light bulbs is 900 hours. A random sample of 15 of its light bulbs resulted in the following lives in hours.                          995 590 510 539 739 917 571 555                          916   728   664   693   708   887   849 At the 10% significance level, test the claim that the sample is from a population with a mean life of 900 hours. Use the P-value method of testing hypotheses. Identify the null and alternative hypotheses,...
A light bulb manufacturer guarantees that the mean life of a certain type of light bulb...
A light bulb manufacturer guarantees that the mean life of a certain type of light bulb is at least 720 hours. A random sample of 51 light bulbs as a mean of 701.6 hours with a population standard deviation of 62 hours. At an α=0.05, can you support the company’s claim using the test statistic? claim is the alternative, reject the null and support claim as test statistic (-2.12) is not in the rejection region defined by the critical value...
A light bulb manufacturer guarantees that the mean life of a certain type of light bulb...
A light bulb manufacturer guarantees that the mean life of a certain type of light bulb is at least 757 hours. A random sample of 22 light bulbs has a mean life of 729 hours. Assume the population is normally distributed and the population standard deviation is 65 hours. At a=0.02​, do you have enough evidence to reject the​ manufacturer's claim. 1. identify null and alternative hypothesis 2.identify region rejections on graph 3.identify standarized test statstics 4. interpret decision
ADVERTISEMENT
Subjects
ADVERTISEMENT
Latest Questions
ADVERTISEMENT