A fitness center is interested in finding a 90% confidence interval for the mean number of days per week that Americans who are members of a fitness club go to their fitness center. Records of 242 members were looked at and their mean number of visits per week was 3.4 and the standard deviation was 1.8. Round answers to 3 decimal places where possible. a. To compute the confidence interval use a ? ✓ distribution. b. With 90% confidence the population mean number of visits per week is between visits. and c. If many groups of 242 randomly selected members are studied, then a different confidence interval would be produced from each group. About percent of these confidence intervals will contain the true population mean number of visits per week and about percent will not contain the true population mean number of visits per week.

The average gold content from an ore sample in 36 different locations is found to be 2.6 grams per ton. a. Find the 95% and 99% confidence intervals for the mean gold content in that area. Assume that the population variance is 0.09.

the weight of an organ in adult males has a bell shaped distribution with a mean of 350 grams and a standard deviation of 50 grams. use the empirical rule to determine the following a. about 99.7% of organs will be between what weights? b. what percentage of organs weighs 300 grams and 400 grams ? Plzz explain both question. Ty

Given below are the sodium contents in milligrams for seven brands of hot dogs rated as “very good” by Consumer Reports.  Find a 99.9% confidence interval for the true mean amount of sodium for “very good” hotdogs. ​​​​400     470​  350​ 365​ 270​ 550​ 530​

Suppose the population standard deviation is  = 5, an SRS of n = 100 is obtained, and the confidence level is chosen to be 99.5%. The margin of error for estimating a mean  is given by:   a. 1.576.   b. 1.165.   c. 1.404.   d. 1.223.

A random sample of 22 Midtown residents in Atlanta has been selected to be studied for their expenditure on theater tickets.  The mean of spending for this group is  $135  with a standard deviation of $39. The mean value of ticket expenditure in Atlanta that has been recorded for the past decade is $120.    Discuss the below points:  1. What is the alternative hypothesis in this assignment?  2. Calculate the standard error of the mean for the study above.    Please provide only typed answer solution no handwritten solution needed allowed

In a survey, 21 people were asked how much they spent on their child's last birthday gift. The results were roughly bell-shaped with a mean of $30.9 and standard deviation of $12.7. Estimate how much a typical parent would spend on their child's birthday gift (use a 90% confidence level). Give your answers to 3 decimal places. Express your answer in the format of a + E. $ 30.9 V + $ 4.770

A data set includes 106 body temperatures of healthy adult humans having a mean of 98.9°F and a standard deviation of 0.63°F. Construct a 99​% confidence interval estimate of the mean body temperature of all healthy humans. What does the sample suggest about the use of 98.6°F as the mean body​ temperature?   Click here to view a t distribution table. LOADING... Click here to view page 1 of the standard normal distribution table. LOADING... Click here to view page 2 of the standard normal distribution table. LOADING...       Question content area bottom Part 1 What is the confidence interval estimate of the population mean μ​?   enter your response here°F<μ<enter your response here°F ​(Round to three decimal places as​ needed.)

Researchers studied the mean egg length (in millimeters) for a bird population. After taking a random sample of eggs, they obtained a 95% confidence interval of (45,60). What is the value of the margin of error? Choose the correct answer below. A. 15 mm B. 52.5 mm O c. 7.5 mm O D. 1.96