Your first step should be putting them in order from least to greatest.
27, 33, 34, 35, 37, 39, 40, 41, and 54. Now to find the median you have to find the middle which in the case would be 37. Now to find the 1st quartile u eliminate the meduan and focus on the lower half of the numbers which would be 27, 33, 34, and 35. If you numbers are even you add and divide by 2. In this case you have to add 34 and 33 and then divide by 2 since they are both in the middle. Your 1st quartile would be 33.5. To find the 3rd quartile you do the same thing as the 1st quartile. Only focus on the upper half now. add both the middles then divide by 2 since there are 2 middles. You 3rd quartile should be 40.5. To fine the inerquartile range you subtract the 1st quartile from the 3rd. so it would be 40.5-33.5 which would give you 7. If you want to fine just the range you would subtract the highest number from the lowest number.
