A bakery is considering buying one of two gas ovens. The bakery requires that the temperature remain constant during a baking operation. A study was conducted to measure the variance in temperature of the ovens during the baking process. The variance in temperature before the thermostat restarted the flame for the Monarch oven was 2 for 21 measurements. The variance for the Kraft oven was 3.1 for 18 measurements. Does this information provide sufficient reason to conclude that there is a difference in the variances for the two ovens? Assume measurements are normally distributed and use a 0.02 level of significance.
(a) Find F. (Give your answer correct to two decimal places.)
(ii) Find the p-value. (Give your answer correct to four decimal places.)
(b) State the appropriate conclusion. Reject the null hypothesis, there is significant evidence to show a difference in variances. Reject the null hypothesis, there is not significant evidence to show a difference in variances. Fail to reject the null hypothesis, there is not significant evidence to show a difference in variances. Fail to reject the null hypothesis, there is significant evidence to show a difference in variances.
You may need to use the appropriate table in Appendix B to answer this question.
A bakery is considering buying one of two gas ovens. The bakery requires that the temperature...
A bakery is considering buying one of two gas ovens. The bakery requires that the temperature remain constant during a baking operation. A study was conducted to measure the variance in temperature of the ovens during the baking process. The variance in temperature before the thermostat restarted the flame for the Monarch oven was 3.9 for 15 measurements. The variance for the Kraft oven was 4.9 for 15 measurements. Does this information provide sufficient reason to conclude that there is...
A bakery is considering buying one of two gas ovens. The bakery requires that the temperature remain constant during a baking operation. A study was conducted to measure the variance in temperature of the ovens during the baking process. The variance in temperature before the thermostat restarted the flame for the Monarch oven was 3.7 for 10 measurements. The variance for the Kraft oven was 4.8 for 24 measurements. Does this information provide sufficient reason to conclude that there is...
1A) Twenty laboratory mice were randomly divided into two groups of 10. Each group was fed according to a prescribed diet. At the end of 3 weeks, the weight gained by each animal was recorded. Do the data in the following table justify the conclusion that the mean weight gained on diet B was greater than the mean weight gained on diet A, at the α = 0.05 level of significance? Assume normality. (Use Diet B - Diet A.) Diet...
A new thermostat has been engineered for the frozen food cases in large supermarkets. Both the old and new thermostats hold temperatures at an average of 25°F. However, it is hoped that the new thermostat might be more dependable in the sense that it will hold temperatures closer to 25°F. One frozen food case was equipped with the new thermostat, and a random sample of 26 temperature readings gave a sample variance of 5.2. Another similar frozen food case was...
A new thermostat has been engineered for the frozen food cases in large supermarkets. Both the old and new thermostats hold temperatures at an average of 25°F. However, it is hoped that the new thermostat might be more dependable in the sense that it will hold temperatures closer to 25°F. One frozen food case was equipped with the new thermostat, and a random sample of 21 temperature readings gave a sample variance of 5.2. Another similar frozen food case was...
A commercial bakery's ovens are designed to bake cakes at a
temperature of 350.0 °F. The ovens are calibrated so that their
temperatures should be normally distributed with a mean of 350.0 °F
and a standard deviation of 4.4 °F. During a recent inspection, the
bakery's quality control supervisor selected a random sample of 12
ovens and recorded their temperatures. She recorded her summary
statistics in the following table.
test of ?=350.0 vs ?≠350.0the assumed standard
deviation=4.4significance level of ?=0.05test...
Forty-one small lots of experimental product were manufactured and tested for the occurrence of a particular indication that is attribute in nature yet causes rejection of the part. Thirty-one lots were made using one particular processing method, and ten lots were made using yet a second processing method. Each lot was equally sampled (n = 30) for the presence of this indication. In practice, optimal processing conditions show little or no occurrence of the indication. Method 1, involving the ten...
Two accounting professors decided to compare the variance of their grading procedures. To accomplish this, they each graded the same 10 exams, with the following results: Mean Grade Standard Deviation Professor 1 79.3 22.4 Professor 2 82.1 12.0 At the 2% level of significance, what is the decision? Multiple Choice A) Reject the null hypothesis and conclude the variances are different. B) Fail to reject the null hypothesis and conclude the variances are different. C) Reject the null hypothesis and...
An employment agency wants to see which of three types of ads in the help-wanted section of local newspapers is the most effective. Three types of ads (big headlines, straightforward, and bold print) were randomly alternated over a period of weeks, and the number of people responding to the ads was noted each week. Type of Advertisement Big Headline Straightforward Bold Print Number of responses (replicates) 26 24 33 30 24 28 45 31 34 35 25 42 40 22...
.A sample of 200 individuals are tested for their blood type is given in the first table, and the results are used to test the hypothesized distribution of blood types. The observed results are given in the second table. At the .05 level of significance, is there sufficient evidence to show that the stated distribution is incorrect? Blood Type A B O AB Percent 0.41 0.06 0.41 0.12 Blood Type A B O AB Number 73 17 84 26 (a)...