Question 5 A consumer agency that proposes that lawyers' rates are too high wanted to estimate the mean hourly rate for all lawyers in New York City. A sample of 70 lawyers taken from New York City showed that the mean hourly rate charged by them is $420. The population standard deviation of hourly charges for all lawyer in New York City is $110. (a) What is point estimate of the corresponding population? (b) Make a 90% confidence interval for the mean hourly charges for all lawyers in New York City, explain your result and what the margin of error of estimate for u is. (c) Construct 98% confidence interval for the mean hourly charges for all lawyers in New York City, explain your result and what is the margin of error of estimate for p.

Example: Home mortgage interest rates for 30-year fixed rate loans vary throughout the country. During the summer of 2000, data available from various parts of the country suggested that the standard deviation of the interest rates was .096. The corresponding variance in interest rates would be (096) =.009216. Consider a follow up study in the summer of 2005. The interest rates for 30 year fixed rate loans at a sample of20 lending institutions had a sample standard deviation of .114. Conduct a hypothesis test using H:o = .009216 to see whether the sample data indicate that the variability in interest rates changed. Use a = .05. What is your conclusion?

A company has a policy of retiring company cars; this policy looks at number of miles driven, purpose of trips, style of car and other features. The distribution of the number of months in service for the fleet of cars is bell-shaped and has a mean of 55 months and a standard deviation of 8 months. Using the empirical rule (as presented in the book), what is the approximate percentage of cars that remain in service between 31 and 47 months?

1) A​ half-century ago, the mean height of women in a particular country in their 20s was 63.7 inches. Assume that the heights of today's women in their 20s are approximately normally distributed with a standard deviation of 2.31 inches. If the mean height today is the same as that of a​ half-century ago, what percentage of all samples of 26 of today's women in their 20s have mean heights of at least 65.04 ​inches?

A company has a policy of retiring company cars; this policy looks at number of miles driven, purpose of trips, style of car and other features. The distribution of the number of months in service for the fleet of cars is bell-shaped and has a mean of 65 months and a standard deviation of 6 months. Using the empirical rule (as presented in the book), what is the approximate percentage of cars that remain in service between 53 and 59 months? Do not enter the percent symbol. ans = 96

A company has a policy of retiring company cars; this policy looks at number of miles driven, purpose of trips, style of car and other features. The distribution of the number of months in service for the fleet of cars is bell-shaped and has a mean of 57 months and a standard deviation of 4 months. Using the empirical rule (as presented in the book), what is the approximate percentage of cars that remain in service between 61 and 65 months?Do not enter the percent symbol.ans = %