MATH 221 FINAL EXAM REVIEW(Version 2) QUESTIONS WITH ANSWERS: DEVRY UNIVERSITY

Final Exam Review Questions – MATH221 You should work each of the following on your own, then review the solutions guide. DO NOT look at the solutions guide first. 1. Determine whether the following are nominal, ordinal, interval, and ratio. a. Daily temperatures in Ripon, WI b. Test scores in statistics class Solution: (a) would be interval as there is no zero while (b) would be ratio as there is a zero. 2. The following numbers represent the weights in pounds of six 7-year old children in Mrs. Jones' 2nd grade class. {25, 60, 51, 47, 49, 45} Find the mean; median; mode; variance; standard deviation. Solution: This would be a sample from the class mean = 46.166 (=AVERAGE) median = 48 (=MEDIAN) mode does not exist (looking at the data) variance = 134.5667 (=VARIANCE.S) standard deviation =11.60029 (=STDEV.S) 3. If the variance is 846, what is the standard deviation? Solution: standard deviation = square root of variance = sqrt(846) = 29.086 4. If we have the following data: 34, 38, 22, 21, 29, 37, 40, 41, 22, 20, 49, 47, 20, 31, 34, 66. Draw a stem and leaf. Discuss the shape of the distribution. Solution: 2 | 2 1 9 2 0 0 3 | 4 8 7 1 4 4 | 0 1 9 7 5 | 6 | 6 This distribution is right skewed (positively skewed) because the “tail” extends to the right. 5. Find the regression equation of the following data