How to Calculate the Median. The median is the middle score of a distribution. Consider this set of numbers: 5, 7, 9, 9, 11. Since you have an odd number of scores, the median would be 9. Now, what happens when you have an even number of scores so there is no single middle score. Consider this set of numbers: 1, 2, 2, 4, 5, 7. Since there are an even number of scores, you need to take the average of the middle two scores.
The platypus (Ornithorhynchus anatinus) also known as the duck-billed platypus is a semiaquatic egg-laying mammal endemic to eastern Australia, including Tasmania.
Several species of duck have brown-plumaged females which can be confused with the female mallard. The female gadwall (A. strepera) has an orange-lined bill, white belly, black and white speculum which is seen as a white square on the wings in flight, and is a smaller bird.