
Mode:The most frequently occurring number or numbers in a set of numbers.
Range:The difference between the greatest and the least in a set of numbers.
Median:In a set of numbers arranged in order from least to greatest, the middle number, or the average of the two middle numbers.
Mean:The average


Mean, median, and mode are three of the most common kinds of "averages".
The "mean" is the "average". How do you find the mean or the average? You add up all the numbers and then divide by the number of numbers. The "median" is the "middle" value in the list of numbers. To find the median, your numbers have to be listed in numerical order, so you may have to rewrite your list first. Find the number in the very middle. The "mode" is the value that occurs most often. If no number is repeated, then there is no mode for the list. The "range" is just the difference between the largest and smallest values.
The median is the middle value, so I'll have to rewrite the list in order:
The mode is the number that is repeated more often than any other.
The largest value in the list is 21, and the smallest is 13, so the range is 21 – 13 = 8.
median: 14 mode: 13 range: 8 ( [the number of data points] + 1) ÷ 2 If that seems confusing, then you can just count in from both ends of the list until you meet in the middle. Remember to do whatever is easier for your. Either way will work.
The median is the middle number. In this example, the numbers are already listed in numerical order, so I don't have to rewrite the list. But there is no "middle" number, because there are an even number of numbers. In this case, the median is the mean (the usual average) of the middle two values:
median: 3 mode: none range: 6
The largest value is 13 and the smallest is 8,
median: 10.5 modes: 10 and 11 range: 5 About the only hard part of finding the mean, median, and mode is keeping straight which "average" is which. Just remember the following:
median: middle value mode: most often
The unknown score is "x". Then the desired average is:
346 + x = 425 x = 79 He needs to get at least a 79 on the last test. 