Explanation: The mean is the average of all the scores, which is found by adding them up and dividing by the number of scores. The mode is the most frequent score, which is the one that occurs the most times. To find the mean and mode for the outlined scores, we can use the following steps:
•Arrange the scores in ascending order: 64, 70, 80, 80, 90, 98, 100
•Add up the scores: 64 + 70 + 80 + 80 + 90 + 98 + 100 = 582
•Divide the sum by the number of scores: 582 / 7 = 83.14
•The mean is 83.14
•Count how many times each score occurs: 64 occurs once, 70 occurs once, 80 occurs twice, 90 occurs once, 98 occurs once, 100 occurs once
•The score that occurs the most times is 80
•The mode is 80
Therefore, the mean and mode for the outlined scores are 83.14 and 80, respectively12 References: 1: Mean, median, and mode review (article) | Khan Academy 2: Mean, Median, and Mode: Measures of Central Tendency - Statistics By Jim