ounsellors of a large university are concerned that students do not have enough sleep. A statistical study was conducted to estimate the average number of hours of sleep per night among students. A 99% confidence interval is computed from a random sample and found to be 7 ± 3. We may conclude that ______________. A. we are 99% confident that the average number of hours of sleep per night of the university students in the sample is between 4 and 10 hours B. if we take many, many additional random samples, and from each computed a 99% confidence interval for u (mean), approximately 99% of these intervals would contain u (mean) C. there is a 99% ch

ch.8 proportions question4 Assume that a sample is used to estimate a population proportion p. Find the 99% confidence interval for a sample of size 143 with 65% successes. Enter your answer as an open-interval (i.e., parentheses) using decimals (not percents) accurate to three decimal places.C.I. =

Ch. 6.1 CI We examine the effect of different inputs on determining the sample size needed to obtain a specific margin of error when finding a confidence interval for a proportion. Find the sample size needed to give, with 95% confidence, a margin of error with +/- 6% when estimating a proportion. Within +/- 4%. Within +/- 1%. (Assume  no prior knowledge about the population proportion p). Comment on the relationship between the sample size and the desired margin of error.

A random sample of 318 students from a large college were asked if they are planning to visit family during Thanksgiving break. Based on this random sample, a 99% confidence interval for the proportion of all students at this college who plan to visit family during Thanksgiving break is 0.78 to 0.98. Which of the following is the correct interpretation of the confidence interval? options: We are 95% confident that the interval from 0.78 to 0.98 captures the true proportion of all students at this college who plan to visit family during Thanksgiving break.   We are 95% confident that the interval from 0.78 to 0.98 captures the true proportion of all students in this sample who plan to visit family during Thanksgiving break.   We are 95% confident that the interval from 0.78 to 0.98 captures the true proportion of all students at this college who said they plan to visit family during Thanksgiving break.   None of these is correct.

(5) You take a random sample from some population and form a 98% confidence interval for the population mean, a. Which quantity is guaranteed to be in the interval you form? A. 0 B. u C. D. 0.98

A clinical trial tests a method designed to increase the probability of conceiving a girl. In the study 520 babies were​ born, and 286of them were girls. Use the sample data to construct a 99​% confidence interval estimate of the percentage of girls born. Based on the​ result, does the method appear to be​ effective?  ________________________<p<______________________ does the method appear to be effective?

QUESTION 17 Construct the indicated confidence interval for the difference between the two population means. Assume that the two samples are independent simple random samples selected from normally distributed populations. Do not assume that the population standard deviations are equal. A researcher was interested in comparing the resting pulse rates of people who exercise regularly and the pulse rates of people who do not exercise regularly. She obtained independent simple random samples of 16 people who do not exercise regularly and 12 people who do exercise regularly. The resting pulse rates (in beats per minute) were recorded and the summary statistics are as follows. Do not exercise regularly Exercise regularly x1 = 723 beats/min x2 = 68.1 beats/min %3D s1 = 10.9 beats/min s2 = 8.2 beats/min ni = 16 n2 = 12 Construct a 95% confidence interval for mu1 - mu2, the difference between the mean pulse rate of people who do not exercise regularly and the mean pulse rate of people who…

Suppose a new treatment for a certain disease is given to a sample of 190 patients. The treatment was successful for 152 of the patients. Assume that these patients are representative of the population of individuals who have this disease. Calculate a 98% confidence interval for the proportion successfully treated. (Round the answers to three decimal places.) ___ to ___