If you would like to know the mean of the data set, you can calculate this using the following steps:
The mean of the data set is the sum of all the data values divided by the number of these values.
12, 17, 16, 10, 20, 13, 14, 14, 12, 12, 19, 18
12 + 17 + 16 + 10 + 20 + 13 + 14 + 14 + 12 + 12 + 19 + 18 = 177
the number of data values: 12
177 / 12 = 14.75
The correct result would be B. 14.75.