COMM 800: HW #4 1. A test is administered to students and the resulting scores are normally distributed. The mean of this test is 75 and the standard deviation is 8. (a) Draw the graph for the...

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COMM 800: HW #4 1. A test is administered to students and the resulting scores are normally distributed. The mean of this test is 75 and the standard deviation is 8. (a) Draw the graph for the distribution of these data and label the locations of the ± 1, ± 2, and ± 3 standard deviations. Also, label the raw scores that correspond to these standard deviation markers. (b) Identify the z-score for each of the following raw scores on this distribution: 83 z = 63 z = 93 z = 75 z = 60 z = (c) Identify the appropriate raw score corresponding to each of the following z-scores: z = +1.50 Raw score = z = 0.00 Raw score = z = -3.00 Raw score = z = -0.25 Raw score = z = +2.33 Raw score = z = -1.75 Raw score = 2. A company has 500 employees, and 60%, percent of them have children. Suppose that we randomly select 4 of these employees. What is the probability that exactly ¾ selected have children? 3. A small college has 800 students, 10% are left handed. What is the probability that if you randomly selected 100 students exactly 3 would be left handed? 4. Assume boys and girls are equal likely and single deliveries only: What is the probability that a couple will have at least one boy if they plan on having 4 children? 5. A study was conducted on students from a particular high school over the last 88 years. The following information was found regrading standardized test used for college admittance. Scores in the SAT test are normally distributed with a mean of 10501050 and a standard deviation of 196196. Scores int he ACT test are normally distributed with a mean of 22.622.6 and a standard deviation of 4.74.7. It is assumed that two tests measure the same amplitude, but use different scales. a. If a student gets an SAT score that is the 5656 percentile, find the actual SAT score, (round answer to a whole number) b. What would be the equivalent ACT score for this student? (round answer to one decimal place) c. If a student gets an SAT score of 14621462, find the equivalent ACT score. (round answer to one decimal place) 6. A correlation of -.74 between variables x and y indicates that…?