The manager of a grocery store has taken a random sample of 169 customers. The average length of time it took these 169 customers to check out was 3 minutes. It is known that the standard deviation of the population of checkout times is 1 minute. The margin of error is 0.151. Find the 95% confidence interval for the true average checkout time (in minutes). O 1 to 5 O 2,849 to 3.151 O 2.873 to 3.127 O 2.988 to 3.012

A statistics class is estimating the mean height of all female students at their college. They collect a random sample of 42 female students and measure their heights. The mean of the sample is 65.3 inches and the sample standard deviation is 5.4 inches. Find the 90% confidence interval for the mean height of all female students in their school? Assume that the distribution of individual female heights at this school is approximately normal. 1. The t value is 1.3025 2. The standard error has a value of -- 3. The margin of error has a value of 4. Find the 90% confidence interval for the mean height of all female students in their school

Assume that the readings at freezing on a bundle of thermometers are normally distributed with a mean of 0°C and a standard deviation of 1.00°C. A single thermometer is randomly selected and tested. Find Pg9, the 69-percentile. This is the temperature reading separating the bottom 69% from the top 31%. P69 = °C

A particular fruit's weights are normally distributed, with a mean of 271 grams and a standard deviation of 28 grams.If you pick 3 fruits at random, then 7% of the time, their mean weight will be greater than how many grams?Give your answer to the nearest gram.

A particular fruit's weights are normally distributed, with a mean of 689 grams and a standard deviation of 13 grams.If you pick 10 fruits at random, then 4% of the time, their mean weight will be greater than how many grams?Give your answer to the nearest gram.

From a sample with n = 12, the mean number of televisions per household is 2 with a standard deviation of 1 television. Using Chebychev's Theorem, determine at least how many of the households have between 0 and 4 televisions. At least of the households have between 0 and 4 televisions. (Simplify your answer.)

The random sample of n=75�=75 yielded a sample mean of x¯=26�¯=26.Assume that we know the population standard deviation is σ=30�=30.    Step 2 of 3 :   Calculate a 95% confidence interval for the population mean. Round your answers to 2 decimals places.

Suppose that the average number of Facebook friends users have is normally distributed with a mean of 112 and a standard deviation of about 48. Assume forty-six individuals are randomly chosen. Answer the following questions. Round all answers to 4 decimal places where possible. 1. the group of 46, find the probability that the average number of friends is more than 123. 2. Find the first quartile for the average number of Facebook friends.

A sample of 8 adult elephants had an average weight of 12,700 pounds. The standard deviation for the sample was 26 pounds. Find the 95% confidence interval of the population mean for the weights of adult elephants. Assume the variable is normally distributed. Use a graphing calculator and round the answers to the nearest whole number.   ? < u < ?