Answer:
Mean, 14; Median, 13.5; Range, 8; Midrange, 15.
Step-by-step explanation:
The mean can be calculated as the sum of all the values divided by the total number of values, so the mean is:
![\begin{gathered} \operatorname{mean}=(11+15+19+12+11+16+11+17)/(8) \\ \operatorname{mean}=(112)/(8) \\ \operatorname{mean}=14 \end{gathered}]()
Then, to find the median, we need to organize the numbers from least to greatest, so:
11 11 11 12 15 16 17 19
1st 2nd 3rd 4th 5th 6th 7th 8th
Now, we median will be in the middle of the date, since there are 8 values, the middle is located at position 4.5, so the median is the mean of the number in the 4th position the number in the 5th position, then:

On the other hand, the range is the difference between the greatest value and the least value, so the range is:

Finally, the midrange is the sum of the greatest value and the least value divided by 2, so:

Therefore, the answer is:
Mean, 14; Median, 13.5; Range, 8; Midrange, 15.