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Median Of A Dataset

Introduction

The median, which means the middle, is the value in the center of a sorted list of numbers. The median gives information about how the numbers are distributed.

Terms

Median - The median is the middle value in a list when values are sorted.

Lesson

To find the median of a set of numbers, first arrange the numbers in ascending order, the median is then the number in the center of the list. If the number of items in the set is odd, there will always be a well-defined median. If however the number of items in the set is even, the median is defined as the mean of the two items in the center of the list.

For example, the median of the set , which contains 7 items, is the 4th item in the list, 5.

To find the median of the even set , take the average of the two center terms, 2 and 4.

Examples

Find the Median (Example #1)

Find the median of the dataset
Right now the numbers are out of order, so it is difficult to tell which number will be in the middle of the list. So first put the numbers in order:
We can see that 5 is in the middle of the list. There are two numbers less than 5, and two numbers greater than 5.
The median of this set is 5

Find The Median (Example #2)

Anthony went to the store every day. On Monday he spent 54 minutes, on Tuesday 50 minutes, on Wednesday 10 minutes, on Thursday 26 minutes, and on Friday 45 minutes. What was the median time that Anthony spent at the store?
Right now the numbers are out of order, so it is difficult to tell which number will be in the middle of the list. So first put the numbers in order:
We can see that 45 is in the middle of the list. There are two numbers less than 45, and two numbers greater than 45.
The median of this set is 45

Find the Median (Example #3)

Find the median of the dataset
Right now the numbers are out of order, so it is difficult to tell which number will be in the middle of the list. So first put the numbers in order:
To find the median in this situation, take the average (mean) of 13 and 14
The median of the set is 13.5

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