Answer:
21.5
Explanation:
1. Line the numbers from least to greatest:
20, 20, 21, 22, 23, 26
2. cross off one from one side then the other
(ex: 20, 20, 21, 22, 23, 26 --> 20, 21, 22, 23 --> 21, 22)
3. the number left is the median, but if there are 2 numbers left do step 4 and 5
4. find the middle of the 2 numbers (ex: 21 and 22's middle is 21.5)
5. The middle of the those 2 numbers is the median (which in this case is 21.5)