Okay, let's take a look at finding central tendencies for the exam grades for a class of students. When we have a set of data, the "measures" of central tendency such as the mean, median and the mode tell us about the center values in the data set.
Let's look at this example,
Here are the average SAT scores from 2007 for ten other universities. Calculate the mean, median and mode. Round to the nearest tenth when necessary.
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The mean is 2137.5. That is the sum (21375) divided by 10 scores.
The median is 2145. Sort the scores in order from smallest to largest. There are 10 scores, so the middle score is the average of the 5th and 6th score. = 2145
The mode is 2100. The mode is the number that occurs most frequently. 2100 occurs twice. If all numbers only occurred once, then there would be no mode.
