How to Find the Mean

Step-by-step solution

1. Add all the values.

   $$4 + 9 + 7 + 8 + 12 = 40$$

   Why: The mean starts with the total of the data set.

2. Count the values.

   $$5\ \text{values}$$

   Why: The divisor is the number of values, not the largest value.

3. Divide the total by the count.

   $$40 \div 5 = 8$$

   Why: The mean is the total shared equally among the values.

Practice problems

Use the same method. Work each problem on paper, then open the answer to check.

1. 1

   $2,\ 4,\ 6$

   Show answer

   $\text{mean } 4$

2. 2

   $10,\ 20,\ 30,\ 40$

   Show answer

   $\text{mean } 25$

3. 3

   $5,\ 5,\ 5,\ 5$

   Show answer

   $\text{mean } 5$

4. 4

   $3,\ 7,\ 8,\ 6$

   Show answer

   $\text{mean } 6$

5. 5

   $1,\ 2,\ 3,\ 4,\ 5$

   Show answer

   $\text{mean } 3$