Final answer:
The median of the provided data set (73, 74, 75, 77, 79, 82, 84, 85, 91) is the middle number since there is an odd number of observations, which is 79. Hence, the answer is B. 79.
Step-by-step explanation:
To find the median of a given set of data, the numbers must first be arranged in ascending order. Once this is done, the median is the middle number in the dataset. If the dataset contains an odd number of observations, the median is simply this middle number. However, if the dataset contains an even number of observations, the median is the average of the two middle numbers.
The provided data set is already in ascending order: 73, 74, 75, 77, 79, 82, 84, 85, 91. As there are 9 numbers, which is odd, the median is the 5th number, which is 79.
Therefore, the correct answer is B. 79.
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