Measures of Central Tendencies

  Measures of central tendencies show us where the middle of a set of data lies.

The three kinds of measures of central tendencies are:

Mean- The total sum of a set of data, divided by how many numbers are in the data   set.  When someone uses the term average, this is often what they are referring to.

Median- The number in the middle of an ordered data set.

Mode- The mode is the number that occurs most often in the data set.

Finding Mean

1. Add all the numbers in the data set.
2. Divide by the amount of numbers in the data set.

Finding Median

1. Put all the numbers in the data set in order (can be from smallest to largest, or largest to smallest, it doesn’t matter).
2. If there are an odd amount of numbers in the data set, use the number that is the one right in the middle of the data set.
3. If there are an even amount of numbers in the data set, add the two middle digits, then divide by two to get the median.

Finding Mode

1. It’s easier if you put the numbers in order.
2. Look to see if there is one number that appears more than the rest of the data set. 
3. It is possible two numbers might appear and equal amount of times.  If that is the case, then they are both the modes.
4. Its is also possible that there is no one number that appears more than the rest.  If that is the case, then the data set has no mode.