In a survey of adults with diabetes, the average body mass index (BMI) in a sample of 1928 women was 31.1 with a standard deviation of 0.2. The BMI in a sample of 1555 men was 30.4, with a standard deviation of 0.6. Construct a 90% confidence interval for the difference in the mean BMI between women and men with diabetes. Interpret the results. Does the confidence interval contradict the claim that the mean BMI is the same for both men and women with diabetes

In an effort to estimate the mean amount spent per customer for dinner at a major Atlanta restaurant, data were collected from 64 randomly selected customers.  The sample mean was calculated as $27.75 with a sample standard deviation of $4.  We wish to develop a 91% confidence interval for the mean amount spent per customer for dinner at this restaurant.  Assume that the standard deviation of the amounts spent by ALL customers is $4.30.   What is the variable of interest?                            ["", "", ""]               And is this variable Quantitative or Qualitative?                            ["", ""]            In other words:  what is the one piece of info we care about for each individual in the population?  Is it a quantitative measurement?  Or do we determine if each individual belongs to a certain category (referred to as success) or not (failure)? If it is a quantitative measurement, then the population is filled with numbers.  Otherwise, the population is filled with…

A study is conducted to find the mean life of a certain manufacturer's car batteries. A random sample of 34 batteries is selected and a mean of 47.5 months with a standard deviation of 7.3 months is found. Find a 95% confidence interval for the mean battery life.

The standard deviation, S, for the annual medical cost of 24 households was found to equal $1689 find a 95% confidence interval for the standard deviation of the annual medical cost for all households. Assume medical costs are normally distributed.

In a poll, 1100 adults in a region were asked about their online vs. in-store clothes shopping. One finding was that 44% of respondents never clothes-shop online. Find and interpret a 95% confidence interval for the proportion of all adults in the region who never clothes-shop online. Click here to view page 1 of the table of areas under the standard normal curve. Click here to view page 2 of the table of areas under the standard normal curve. The 95% confidence interval is from to (Round to three decimal places as needed.)

From a sample of 37 graduate students, the mean number of months of work experience prior to entering an MBA program was 36.63. The national standard deviation is known to be 19 months. What is a 90% confidence interval for the population mean? A 90% confidence interval for the population mean is 10 (Use ascending order. Round to two decimal places as needed.) ...

In a random sample of 17 people, the mean commute time to work was 30.2 minutes and the standard deviation was 7.1 minutes. Assume the population is normally distributed and use a t- distribution to construct a 95% confidence interval for the population mean y. What is the margin of error of y? Interpret the results.

A 95% confidence interval for the mean weight of bags of potato chips packed by a machine was found to be from 15.9 oz. to 16.04 oz. What was the margin of error?

In September a biological research team caught, weighed, and released a random sample of 24 chipmunks in Rocky Mountain National Park. The mean of the sample weights was x-bar = 8.7 oz. with sample standard deviation s = 1.4 oz. Find a 90% confidence interval for the mean September weight of all chipmunks in Rocky Mountain National Park.

In a large city, you pick a sample of 30 of lawn mowings during summer. The standard deviation is known to be  11.4.  The margin of error for a 90% confidence interval will be