Answer: 17.5
Step-by-step explanation: The median is the middle number in the data set when the data set is written from least to greatest.
Notice that our numbers are already written from least to greatest.
Notice however that there are two numbers that appear in the middle so to find the median, we take the sum of the numbers and divide by 2.
So we take 17 + 18 which gives us 35.
Now we divide 35 by 2 to get 17.5.
So the median of this data set is 17.5.