# How do you find the variance of a set of numbers?

1. Find the arithmetic mean (average)

2. Find the distance of each number from the mean (x-the mean=?)

3. Square each number

4. Add up all of the squares

5. Divide the final sum by the original mean

EX: Set: 1, 3, 4, 5, 7

1. 1 + 3 + 4 + 5 + 7 = 20 / 5 = **4**

2. 1-4=-**3** 3-4=-**1** 4-4=**0** 5-4=**1**
7-4=**3**

3. 3*3=**9** 1*1=**1** 0*0=**0** 1*1=**1**
3*3=**9**

4. 9 + 1 + 0 + 1 + 9 = **20**

5. 20 / 4 = **5**

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