Answer:

To find the mean, median, and mode of the given set of numbers, let's calculate each value:

Mean:

To find the mean, we add up all the numbers and divide the sum by the total count of numbers.

Mean = (70 + 74 + 71 + 73 + 75 + 80 + 83 + 81 + 75 + 86 + 30 + 80 + 78 + 85 + 83) / 15

Mean = 1080 / 15

Mean = 72

Median:

To find the median, we arrange the numbers in ascending order and find the middle value.

30, 70, 71, 73, 74, 75, 75, 78, 80, 81, 83, 83, 85, 86

Since we have 15 numbers, the median will be the average of the two middle values, which are the 7th and 8th numbers.

Median = (75 + 78) / 2

Median = 76.5

Mode:

The mode is the value(s) that appear(s) most frequently in the given set of numbers.

In this case, there is no value that appears more than once, so there is no mode.

Therefore, the values are:

Mean = 72

Median = 76.5

Mode = N/A (No mode)