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We are testing the null hypothesis

A World Campus administrator wants to test if more than 60% of all World Campus undergraduate students are first-generation college students. In a random sample of 75 World Campus undergraduate students, 51 are first-generation college students. What is the test statistic to test the administrator’s question? 

Please note that this question consists of three parts. Show all your work/explanation. Just giving the answer without adequate work/explanation may result in zero for the question.  The shoulder width of an adult male is normally distributed with a mean of 16.2 in and a standard deviation of 1.6 in. The standard coach seat on a plane is 17.2 inches wide. What percentage of adult males fit in such a seat without overflow? An engineer wants to design an airline chair to fit 98% of the male passengers. What should be the minimum width of the chair? Find the range, centered at the population mean, that contains 90% of the adult male’s shoulder breadths.

State if each of the below statement is either true or false.  

Please note that this question consists of six parts. Show all your work/explanation. Just giving the answer without adequate work/explanation may result in zero for the question.  A company makes insulation shields for electrical wires using four different types of machines. The company wants to evaluate the variation in the inside diameter dimensions of the shields produced by the machines. A quality engineer at the company randomly selects shields produced by each of the machines and records the inside diameter of each shield (in millimeters). She wants to determine whether or not the mean inside diameter is the same for the four machines. Use the provided partial output to answer the following questions. Write down the null and alternative hypotheses for testing whether or not the mean inside diameter is the same for the four machines. Clearly define any parameters you might use. Compute the Error Degrees of Freedom missing in the ANOVA output. Compute the Treatment Mean Square missing in the ANOVA output. Compute the F-value missing in the ANOVA output. At 5% significant level, is there sufficient evidence to claim that the mean inside diameter is different for at least one of the four machines. Explain your answer. The output for Tukey pairwise comparisons is given below. Based on the output Based on the grouping information output, is the mean inside diameter significantly different for machines B and C? Explain your answer. Based on Tukey simultaneous CIs, for which machines the mean inside diameter is significantly different from machine A? Explain your answer.

The scores on a test administered each year to many high school students are normally distributed with mean 515 and standard deviation 130. What percentage of scores are  above 645? [fill1] between 385 and 775? [fill2]

When testing 

Investigators study the effect of a drug at 7 different doses. 10 patients are assigned at random to each treatment (dose). Their blood pressure is recorded after a course of taking the drug. ANOVA is used to test if the mean blood pressure is different for at least one dose. What are the treatment degrees of freedom?

Researchers want to evaluate the possible side effects of a drug. It is suspected that the drug may lead to an elevation in the blood pressure of users of the drug. A preliminary study of two groups of patients, one receiving the drug and the other receiving a placebo, provides the following information on the systolic blood pressure (in mm Hg) of the two groups: mean standard deviation Placebo 129.9 18.5 Drug 135.5 18.7 Assume that both groups have systolic blood pressures that have a normal distribution. The correct null and alternative hypotheses to answer this question are

A company rents equipment from firm A 75% of the time and from firm B 25% of the time. 90% of equipment from firm A is in good condition. Only 65% of equipment from firm B is in good condition. If a rented equipment is not in a good condition, what is the probability it came from firm A?