what is the range?median?average

Range and median are different kinds of "average". There are others. Here is a summary.

Consider the set of numbers 80, 90, 90, 100, 85, 90. They could be math grades, for example.

The MEAN is the arithmetic average, the average you are probably used to finding for a set of numbers - add up the numbers and divide by how many there are: (80 + 90 + 90 + 100 + 85 + 90) / 6 = 89 1/6.

The MEDIAN is the number in the middle. In order to find the median, you have to put the values in order from lowest to highest, then find the number that is exactly in the middle: 80 85 90 90 90 100

since there is an even number of values, the MEDIAN is between these two underlined red numbers, or it is 90. Notice that there is exactly the same number of values ABOVE the median as BELOW it.

The MODE is the value that occurs most often. In this case, since there are 3 90's, the mode is 90. A set of data can have more than one mode.

The RANGE is the difference between the lowest and highest values. In this case 100 - 80 = 20, so the range is 20. The range tells you something about how spread out the data are. Data with large ranges tend to be more spread out.