Completed quickly and followed instructions given. Grammar, spelling, etc. was all good as well. Thank you so much! Will hire in the future.
1. The quality control manager at a light-bulb factory needs to estimate the mean life of a new type of light-bulb. The population standard deviation is assumed to be 65 hours. A random sample of 40 light-bulbs shows a sample mean life of 505 hours. Construct and explain a 95% confidence interval estimate of the population mean life of the new light-bulb.
2. A survey of first-time home buyers found that the sample mean annual income was $42,300. Assume that the survey used a sample of 27 first-time home buyers and that the sample standard deviation was $1,125. Compute and explain a 90% confidence interval estimate of the population mean.
3. A telephone poll of 800 American adults asked “where would you rather go in your spare time?” One response, by 275 adults, was “the Mall”. Compute and explain a 98% confidence interval estimate of the proportion of all American adults who would respond “the Mall”.
4. For problem #1 above, what size sample would be needed to achieve a margin of error of 15 hours or less?
Show more
Delivering a high-quality product at a reasonable price is not enough anymore.
That’s why we have developed 5 beneficial guarantees that will make your experience with our service enjoyable, easy, and safe.
You have to be 100% sure of the quality of your product to give a money-back guarantee. This describes us perfectly. Make sure that this guarantee is totally transparent.
Read moreEach paper is composed from scratch, according to your instructions. It is then checked by our plagiarism-detection software. There is no gap where plagiarism could squeeze in.
Read moreThanks to our free revisions, there is no way for you to be unsatisfied. We will work on your paper until you are completely happy with the result.
Read moreYour email is safe, as we store it according to international data protection rules. Your bank details are secure, as we use only reliable payment systems.
Read moreBy sending us your money, you buy the service we provide. Check out our terms and conditions if you prefer business talks to be laid out in official language.
Read more