To calculate the variance follow these steps:
1. Work out the Mean
2. Then for each number: subtract the Mean and square the result .
3. Then work out the average of those squared differences.
The data are 10, 11, 12, 13, 14, 18
The first step find the mean
The mean = sum of data/number of data
The sum = 10 + 11 + 12+ 13 +14 + 18 = 78
The number =