Based on consumer reports, replacement times for TV sets are normally distributed with a mean of...

Transcribed Image Text:

Based on consumer reports, replacement times for TV sets are normally distributed with a mean of 8.2 years and a standard deviation of 1.1 years, and replacement times for CD players are normally distributed with a mean of 7.1 years and a standard deviation of 1.4 years. a. What percent of TV sets have a replacement time between 6 years and 7 years? (Round to three decimal places) b. What percent of TV sets have a replacement time of more than 10 years? (Round to three decimal places) c. What percent of CD players have a replacement time of more than 10 years? (Round to three decimal places) d. What replacement time for CD players would represent the 90th percentile? (Round to one decimal place) e. Which replacement time is in the higher percentile: a TV replacement time of 8.5 years or a CD player replacement time of 7.3 years? The Internal Revenue Service reports that the mean federal income tax paid in 2007 was $7908 with a standard deviation of $5000. a. In this situation, could the Central Limit Theorem be applied to a sample of 1000 taxpayers? , because b. If a sample of 1000 taxpayers is randomly selected, state the mean and standard deviation of the sampling distribution of the mean according to the Central Limit Theorem. (round to the nearest integer) (round to the nearest tenth) c. Find the probability that 1000 randomly selected taxpayers will have a mean that is less than $8000. (round to the nearest hundreth) d. Suppose a sample of 1000 taxpayers has a mean of $8300 for federal income tax paid. Using the appropriate probability, determine if this is a significantly high sample mean. (Hint: How likely is to get a sample mean at least a large as what was observed in the sample?) Probability: (round to four decimal places) The observed sample mean significant. Based on consumer reports, replacement times for TV sets are normally distributed with a mean of 8.2 years and a standard deviation of 1.1 years, and replacement times for CD players are normally distributed with a mean of 7.1 years and a standard deviation of 1.4 years. a. What percent of TV sets have a replacement time between 6 years and 7 years? (Round to three decimal places) b. What percent of TV sets have a replacement time of more than 10 years? (Round to three decimal places) c. What percent of CD players have a replacement time of more than 10 years? (Round to three decimal places) d. What replacement time for CD players would represent the 90th percentile? (Round to one decimal place) e. Which replacement time is in the higher percentile: a TV replacement time of 8.5 years or a CD player replacement time of 7.3 years? The Internal Revenue Service reports that the mean federal income tax paid in 2007 was $7908 with a standard deviation of $5000. a. In this situation, could the Central Limit Theorem be applied to a sample of 1000 taxpayers? , because b. If a sample of 1000 taxpayers is randomly selected, state the mean and standard deviation of the sampling distribution of the mean according to the Central Limit Theorem. (round to the nearest integer) (round to the nearest tenth) c. Find the probability that 1000 randomly selected taxpayers will have a mean that is less than $8000. (round to the nearest hundreth) d. Suppose a sample of 1000 taxpayers has a mean of $8300 for federal income tax paid. Using the appropriate probability, determine if this is a significantly high sample mean. (Hint: How likely is to get a sample mean at least a large as what was observed in the sample?) Probability: (round to four decimal places) The observed sample mean significant.