Enter the mean, the total score, and the standard deviation into the Z Ratio Calculator. The calculator will evaluate and display the Z Ratio.

## Z Ratio Formula

The following formula is used to calculate the Z Ratio.

**ZR = (M-S) / SD**

- Where ZR is the Z Ratio ( )
- M is the mean
- S is the total score
- SD is the standard deviation

## How to Calculate Z Ratio?

The following example problems outline how to calculate Z Ratio.

**Example Problem #1**

- First, determine the mean.
- The mean is calculated to be : 5.

- Next, determine the total score.
- The total score is measured to be: 2.

- Next, determine the standard deviation.
- The standard deviation is found to be: 1.5.

- Finally, calculate the Z Ratio using the formula above:

ZR = (M-S) / SD

The values given above are inserted into the equation below and the solution is calculated:

ZR = (5-2) / 1.5 = 2

**Example Problem #2**

The variables required for this problem are provided below:

mean = 6

total score = 4

standard deviation = 1.35

Test your knowledge using the equation and check your answer with the calculator above.

ZR = (M-S) / SD =** **( )