Range Variance Standard deviation [indicates with mean: if the data distribution is normal, 68% of the data is within 1 standard deviation; 95% is within 2 standard deviations, 99.7% is within 3 standard deviations]

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The times taken in seconds by a group of students to complete an online exercise are listed as follows. 31,34,41,33,29,31,39,35,30,40 (a) Find the median time. (b) Calculate the interquartile range.

The chart to the right shows that a professor's grading distribution is bell shaped, or normally shaped. The mean of the distribution is 74 and the standard deviation is 9. Using a Continuous Variable Normal Bell Distribution Model, calculate the minimum test score needed to score in the top 5% of the class. Complete your work in the worksheet by listing the formula inputs, labels for the formula inputs and make your calculations with formulas. This test problem is similar to what you studied in video # 32, 33 and 34 and homework problems # 17, 21 and 23. Relative Frequency Frequency Professor looks at all test score for a particular test (this is population data), and observes: 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Mean = 74 Median = 74 Mode = 73 SD=9 0 0 0 up to 10 up 10 to 20 0 20 up to 30 0 30 up to 40 2 40 up to 50 29 50 up to 60 X = Score 112 60 up to 70 225 70 up to 80 111 80 up to 90 21 2 90 up 100 up to 100 to 110

On an exam, there is a mean score of 80 with a standard deviation of 12 If each exam is multiplied by 1.2, what will mean and standard deviation be? Please show computation