Statistics module 3 case.docx - Makayla Roberson Math...

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Makayla Roberson Math statistics 101 1. The final exam scores listed below are from one section of MATH 200. How many scores were within one standard deviation of the mean? How many scores were within two standard deviations of the mean? 99 34 86 57 73 85 91 93 46 96 88 79 68 85 89 Answer: sum = 1115 divided by 16 = 69.69 P(X<x) 2. The scores for math test #3 were normally distributed. If 15 students had a mean score of 74.8% and a standard deviation of 7.57, how many students scored above an 85%? Answer: x=15 m=74.8 sd=7.57 Calculate Z-score: Z= 85-74.8/7.57 = 1.35 The percentage of students the scored above 85% is P(Z>1.35) is 8.85%. Find the number of students who scored above 85% is percentages of students above 85% x total number of students = 8.85% x 15 = 1.35 =1 student is estimated to score above 85% on the test. 3. If you know the standard deviation, how do you find the variance? To find the variance, divide the sum.
4. To get the best deal on a stereo system, Louis called 8 out of 20 appliance stores in his neighborhood and asked for the cost of a specific model. Below is the sample data set of prices he
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