Answer:
12.54
Explanation:
When finding the mean, first you add all the numbers in the data:
9+14+14+9+20+6+8+19+17+13+9=138
And then you divide it by the following numbers in the set. In this data set, since there are 11 numbers, you would divide 138 by 11.
138\11=12.5454545
So the answer would be 12.54 if your rounding to the nearest hundred. If your rounding it by a whole number, it would be 13.