Exam (elaborations) MATH 225N Week 8 Statistics Final Exam 2021

Week 8 Final Examscored 128 out of 160= 80% QUESTION 1 Of the following pairs of events, which pair has mutually exclusive events? rolling a sum greater than 7 from two rolls of a standard die and rolling a 4 for the first throw drawing a 2 and drawing a 4 with replacement from a standard deck of cards rolling a sum of 9 from two rolls of a standard die and rolling a 2 for the first roll drawing a red card and then drawing a black card with replacement from a standard deck of cards QUESTION 2 Hugo averages 41 words per minute on a typing test with a standard deviation of 7.5 words per minute. Suppose Hugo's words per minute on a typing test are normally distributed. Let X= the number of words per minute on a typing test. Then, X∼N(41,7.5). Suppose Hugo types 45 words per minute in a typing test on Wednesday. The z-score when x=45 is ________. This z-score tells you that x=45 is ________ standard deviations to the ________ (right/left) of the mean, ________. Correctly fill in the blanks in the statement above. Select the correct answer below: Suppose Hugo types 45 words per minute in a typing test on Wednesday. The zscore when x=45 is −0.533. This z-score tells you that x=45 is 0.533 standard deviations to the left of the mean, 41. Suppose Hugo types 45 words per minute in a typing test on Wednesday. The zscore when x=45 is −0.381. This z-score tells you that x=45 is 0.381 standard deviations to the left of the mean, 41. Suppose Hugo types 45 words per minute in a typing test on Wednesday. The zscore when x=45 is 0.381. This z-score tells you that x=45 is 0.381 standard deviations to the right of the mean, 41.