The mean finish time for a yearly amateur auto race was 186.62 minutes with a standard deviation of 0.391 minute. The winning car, driven by Hank, finished in 185.95 minutes. The previous year's race had a mean finishing time of 111.8 with a standard deviation of 0.142 minute. The winning car that year, driven by Rita, finished in 111.49 minutes. Find their respective z-scores. Who had the more convincing victory? Hank had a finish time with a z-score of Rita had a finish time with a z-score of (Round to two decimal places as needed.) Which driver had a more convincing victory? A. Rita had a more convincing victory because of a lower z-score. B. Hank a more convincing victory because of a higher z-score. C. Rita had a more convincing victory because of a higher z-score. D. Hank a more convincing victory because of a lower z-score.
Added by Jeffrey M.
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The z-score is calculated by subtracting the mean from the individual score and then dividing by the standard deviation. For Hank: Z = (185.95 - 186.62) / 0.391 = -1.71 For Rita: Show more…
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