The median of a data set is the 'middle number'. You can find the median by listing the given numbers from least to greatest (left to right) and finding the middle number.
8, 10, 10, 10, 11, 12, 14, 14, 15, 16, 17, 18
Cross one out on each side before getting to your last number that should be in the middle.
The middle numbers are: 12 and 14. If it was only one number, we could already have the answer, but since it is two numbers in the middle, we need to add them up and divide by 2.
12 + 14 = 26
26 ÷ 2 = 13
So, the median of the data set is: 13.
