question archive A university official believes that, of students who withdraw from the university, 60% do so within one week of the deadline
A university official believes that, of students who withdraw from the university, 60% do so within one week of the deadline
Subject:StatisticsPrice: Bought3
A university official believes that, of students who withdraw from the university, 60% do so within one week of the deadline. In a random sample of 150 students who withdrew from the university it was found that 99 of them had withdrawn within one week of the deadline. At the .01 level of significance, does it appear that the university official is incorrect?
(a) (3 points.) 0H : ____________________ AH :____________________
(b) (4 points.) z = ____________________
(c) (4 points.) P-value = ____________________
(d) (3 points.) Circle one: Accept 0H Reject 0H
Q42. An elementary school curriculum specialist claims that, on average, a student needs 10 minutes to do a particular assignment. A teacher believes that, on average, students require longer than the designer claims. The teacher observed the time needed for each student in a random sample of 16 to complete the assignment. It was found that the students needed an average of 12 minutes with a standard deviation of 3 minutes. Conduct the test of interest at the .10 level of significance. (You may assume that assignment completion times are approximately normally distributed.)
(a) (3 points.) 0H : ____________________ AH :____________________
(b) (4 points.) t = ____________________
(c) (4 points.) Bound the p-value as closely as possible:
__________ < p-value < _________
(d) (3 points.) Circle one: Accept 0H Reject 0H
SHOW ALL WORK.
Q43. (6 points.) In order to compare the download speeds of internet service in a particular city, two independent random samples were collected. A random sample of 36 cable internet users (group #1) showed an average download benchmark of 15 MB with a standard deviation of 4 MB while a sample of 50 DSL internet customers (group 2) showed an average download benchmark of 12 MB with a standard deviation of 2 MB. Obtain a 90% confidence interval for the population difference in the average download benchmark amounts. (Be sure to work out both endpoints to numeric values.)
Q44. At a particular restaurant, the weight of an order of French fries approximately follows a bell-shaped (normal) frequency curve with a mean of 150 grams and a standard deviation of 4 grams.
(a) (8 points.) Fifteen percent (15%) of orders weight more than _____ grams.
(b) (8 points.) The 16th percentile order weight amounts is 146 grams. The weight of _____ percent of orders is between 146 grams and 157 grams.
