Mean: to find the mean you add all the data and then divide into the number of data.
number of data: 8

Mean: 12
Median: to find the meadian order the data from least to greather and then select the middle data (as the total of data is 8 you select the two data in the middle and calculate the average)
Data ordered:

Middle data: 11 and 11:

Median: 11
Mode: To find the mode you look for the data that repeat the most.
Mode: As the number 10, 11 and 17 repeats all 2 times. There data set is trimodal: Mode: 10, 11 and 1711 and 17
Range: To find the range of a data set you substract from the greatest value the least value:
Greatest value: 17
Least value: 6

Range: 11