Final answer:
The median of the data set {75, 65, 100, 80, 85, 75, 100} is 80 after arranging the numbers in order, which makes the answer A) 80.
Step-by-step explanation:
To find the median of a data set, arrange the numbers in numerical order and then identify the middle number. If the data set has an odd number of values, the median is the one directly in the center. If there is an even number of values, the median is found by taking the average of the two middle numbers. For the given data set {75, 65, 100, 80, 85, 75, 100}, let's arrange it in order: {65, 75, 75, 80, 85, 100, 100}. This data set has seven numbers, so the median is the fourth value, which is 80. The correct answer is A) 80.