It currently takes users a mean of 44 minutes to install the most popular computer program made by RodeTech, a software design company. After changes have been made to the program, the company executives want to know if the new mean is now different from 44 minutes so that they can change their advertising accordingly. A simple random sample of 51 new customers are asked to time how long it takes for them to install the software. The sample mean is 47.8 minutes with a standard deviation of 10.2 minutes. Perform a hypothesis test at the 0.10 level of significance to see if the mean installation time has changed. Step 3 of 3: Draw a conclusion and interpret the decision. Answer Tables Keypad Keyboard Shortcut O We reject the null hypothesis and conclude that there is sufficient evidence at a 0.10 level of significance that the new mean installation time is different from 44 minutes and that RodeTech may need to change their advertising. O We fail to reject the null hypothesis and conclude that there is sufficient evidence at a 0.10 level of significance that the new mean installation time is different from 44 minutes and that RodeTech may need to change their advertising. O We fail to reject the null hypothesis and conclude that there is insufficient evidence at a 0.10 level of significance that the new mean installation time is different from 44 minutes and that RodeTech may need to change their advertising. We reject the null hypothesis and conclude that there is insufficient evidence at a 0.10 level of significance that the new mean installation time is different from 44 minutes and that RodeTech may need to change their advertising.

In a normally distributed data set a mean of 55 where 95% of the data fall between 47.4 and 62.6, what would be the standard deviation of that data set?

A nutritionist conducted a study on the eating patterns of early adolescent boys and girls. Calorie intake is normally distributed for both boys and girls. The population means are 3300 calories per day for boys and 2900 calories per day for girls. The population standard deviations are 790 for boys and 720 for girls. The nutritionist believes that children may have an eating disorder if they are in the bottom 2% the distribution. Based on this, if a child’s intake is1600 calories per day, should the nutritionist be concerned that this child may have an eating disorder? (Compute for each gender separately). Does it make a difference if this child is a boy or a girl? Explain your answer.  What proportion of girls consume between 2000 and 2400 calories per day?        Is the proportion of boys who consume between 2000 and 2400 calories per day the same, higher, or lower than the proportion of girls who consume between 2000 and 2400 calories per day? Explain your answer.

A bank loan officer rates applicants for credit. The ratings can be described by a normal model with a mean of 200 and a standard deviation of 50. If an applicant is randomly selected, what percentage can be expected to be between 200 and 275?

The results of a common standardized test used in psychology research is designed so that the population mean is 115 and the standard deviation is 30. A subject earns a score of 199. What is the z-score for this raw score?

Lucas and Alex began arguing about who did better on their tests, but they couldn't decide who did better given that they took different tests. Lucas took a test in Math and earned a 73.4, and Alex took a test in English and earned a 70.5. Use the fact that all the students' test grades in the Math class had a mean of 74.1 and a standard deviation of 11.3, and all the students' test grades in English had a mean of 60.9 and a standard deviation of 8.1 to answer the following questions.a) Calculate the z-score for Lucas's test grade.z=z=b) Calculate the z-score for Alex's test grade.z=z=

The average chef at a restaurant earns $17 an hour with a deviation of $1.75. What are the chances that someone is earning more than $20 an hour?

Myers Business Systems is evaluating the introduction of a new product. The possible levels of unit sales and the probabilities of their occurrence are given next Possible Market Reaction Low response Moderate response High response Very high response Sales in Units 25 35 40 70 a. What is the expected value of unit sales for the new product? Note: Do not round Intermediate calculations and round your answer to the nearest whole unit. Expected value units Standard deviation Probabilities 0.40 0,20 0.10 0.30 b. What is the standard deviation of unit sales? Note: Do not round Intermediate calculations. Round your answer to 2 decimal places. units

Suppose 36% of movie goers say comedy is their favorite genre. If a random sample of 120 movie goers is taken, what are the mean and standard deviation of the number of movie goers that prefer comedy?

April and Heather began arguing about who did better on their tests, but they couldn't decide who did better given that they took different tests. April took a test in Science and earned a 74.4, and Heather took a test in English and earned a 69.7. Use the fact that all the students' test grades in the Science class had a mean of 71.3 and a standard deviation of 8.9, and all the students' test grades in English had a mean of 60.5 and a standard deviation of 8.5 to answer the following questions. a) Calculate the z-score for April's test grade. b) Calculate the z-score for Heather's test grade. c) Which person did relatively better? April Heather O They did equally well. Submit Question logi $22 *3 F4 F8 7. 8. %4