To start you have to order the numbers from least to greatest, getting 40, 75, 80, 80, 81, 84, 88, 90, 92, 100, 100. Then you would take out the end number on each side, getting 75, 80, 80, 81, 84, 88, 90, 92, 100. You continue taking numbers off the end until you get to the middle number, or the middle two numbers if there is an even amount of numbers, which would give you the median 84. If you had an even amount of numbers and got down to two numbers, you would add them together and divide them by two.