QMB exam 2 with answers

# QMB exam 2 with answers - Fall Exam 2 Use this information...

This preview shows pages 1–3. Sign up to view the full content.

Fall Exam 2 Use this information for problems 1-4 The manufacturer of the DentaShine brand of chewing gum claims that more than 70% of dentists surveyed prefer their type of gum. You decide to test their claim. 3. Regardless of what you actually got for question 2, assume you calculated that the standard error was SE = .033. If so, what is the computed value for the test statistic Z CALC ? 1.40 1.80 2.20 2.60 Choose one answer: <-------+-------+-------+-------+-------> A B C D E A Answer: 4. Regardless of what you actually got for question 3 , assume you calculated that the standardized value of the test statistic was Z CALC = 2.30. If so, what is the p-value for the test? (Assume the hypotheses are stated as in answer D to question 1.) 1.0 .10 .05 .025 .01 0.0 Choose one answer: +-------+-------+-------+-------+-------+ A B C D E When you look up Z=2.30 in our tables, you get a probability of .4893 in the middle of the distribution. To get the tail probability subtract .5 - .4893 = .0107. That is the p-value. Use this info to answer question 5: The use of preservatives by food processors has become a controversial issue. Suppose two preservatives have been extensively tested and determined safe for use in meats. ` A processor wants to compare the preservatives for their effects on retarding spoilage. He treats 21 rib roasts with preservative A and another 21 roasts with preservative B. The number of hours until spoilage begins is recorded for each of the 42 roasts. The results are summarized below. Preservative A Preservative B 130.6 Average 120.1 7.03 Std. Dev. 6.19 5.Suppose you are going to estimate the average difference until spoilage begins by computing a 95% interval for( μ A - B ) under the assumption that the two population variances are about equal; that is, assuming σ 2 A 2 B . In doing so, what is your estimate of the pooled-sample standard deviation, S p ? 6.00 6.40 6.80 7.20 Choose one answer: <-------+-------+-------+-------+-------> A B C D E Answer: G

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Use for questions 9 and 10: A buyer for a manufacturing plant suspects that his primary supplier of raw materials is overcharging. In order to determine if his suspicion is correct, he contacts a second supplier and asks for prices on various materials. He wants to compare these prices with those of his primary supplier. The data collected is presented in the table below, with some summary statistics presented. Values are in dollars. Raw Material K1 C2 M7 C4 M2 K6 Average Std. Dev. Primary Supplier 61 55 43 90 55 60 60.667 15.731 Second Supplier 45 47 32 77 37 54 48.667 15.883 Difference 16 8 11 13 18 6 12.000 4.604 9. Instead of using a confidence interval, suppose we test the hypothesis H 0 : ( μ Prime - Second ) = D 0 versus H 1 : D > 0 . What is computed value of the test statistic for this procedure? 1.5
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 10

QMB exam 2 with answers - Fall Exam 2 Use this information...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online