Identify the outlier in the following list. then find the mean and median of the list with and without the outlier. 11, 12, 16, 8, 17, 110, 6

The outlier is 110.
How do we know this?

Take a look at all of the numbers. 11, 12,16 blah, 8,17,blah blah,6,blah blah blah, 110WOW 110 where did that come from?! ;)
We had all numbers in the range of 6-17 and all of a sudden we have a huge number that clearly does not fit in with the rest. 

The mean of the list without the outlier: 11.7
To find mean we take the average of all of the numbers combined.
First we add up the numbers... 11+12+16+8+17+6=70
Then we divide that by how many numbers there are. 70/6=11.7

Mean with the outlier (110): 25.7
Same steps apply.
11+12+16+8+17+6+110=180
180/7=25.7

There is no mode however because no number is more popular than another. No number appears more times than the other numbers.

Hope this helped!