From a large number of actuarial exam scores, a random sample of  275  scores is selected, and it is found that  187  of these  275  are passing scores. Based on this sample, find a  90%

find the t sub alpha/2 when n=23 for the 95% confidence interval.

A random sample of 500 patients with diabetes were weighed before and after switching to a new drug and the change in their weight is computed for each patient. The resulting 90% confidence interval for the average change in the weight of diabetes patients is (1, 5) expressed in pounds. Which of the following can be the 95% confidence interval generated from the same data?

A researcher surveys a group of college students to determine the negative life events that they experienced in the past 5 years and their current feeling of well-being. For N = 18 participants with 2 or fewer negative experiences, the average well-being score was X = 42 with SS = 398. For the N = 16 participants with 5 to 10 negative experiences the average score is X = 48.6 with SS = 370. Construct a 95% confidence interval for the difference between the population means for the two groups.

We wish to estimate what percent of adult residents in a certain county are parents. Out of 100 adult residents sampled, 48 had kids. Based on this, construct a 90% confidence interval for the proportion ππ of adult residents who are parents in this county.

A random sample of n₁ = 224 people who live in a city were selected and 90 identified as a "dog person." A random sample of n₂ = 95 people who live in a rural area were selected and 61 identified as a "dog person." Find the 95% confidence interval for the difference in the proportion of people that live in a city who identify as a "dog person" and the proportion of people that live in a rural area who identify as a "dog person." Round answers to to 4 decimal places. P1 P2

A random sample of n₁ = 269 people who live in a city were selected and 88 identified as a "dog person." A random sample of n2 = 90 people who live in a rural area were selected and 70 identified as a "dog person." Find the 99% confidence interval for the difference in the proportion of people that live in a city who identify as a "dog person" and the proportion of people that live in a rural area who identify as a "dog person." Round answers to to 4 decimal places. < P1 P2 <

In order to estimate the average GPA of all students at SCC, we selected a random sample of 36 students and found that their average GPA is 2.1 with a s. d. of 0.8.Construct a 95% confidence interval for the average GPA of all students at SCC.

In a science fair​ project, Emily conducted an experiment in which she tested professional touch therapists to see if they could sense her energy field. She flipped a coin to select either her right hand or her left​ hand, and then she asked the therapists to identify the selected hand by placing their hand just under​ Emily's hand without seeing it and without touching it. Among 337 trials, the touch therapists were correct 163 times.  Using​ Emily's sample​ results, construct a 95​% confidence interval estimate of the proportion of correct responses made by touch therapists. (round to 3 decimal places)

A random sample of n1n1  = 235 people who live in a city were selected and 79 identified as a "dog person." A random sample of n2n2  = 93 people who live in a rural area were selected and 67 identified as a "dog person." Find the 99% confidence interval for the difference in the proportion of people that live in a city who identify as a "dog person" and the proportion of people that live in a rural area who identify as a "dog person." Round answers to to 4 decimal places. < p1−p2<