Yet there is considerable opposition to the use of genetically modified plants for food production and other uses. Genetic engineering offers a time-saving method for producing larger, higher-quality crops with less effort and expense. You are a tomato farmer whose crops are threatened by a persistent species of beetle. 2  Each year, you spend large sums of money for pesticides to protect your crops.
To calculate the variance follow these steps: 1  Work out the Mean (the simple average of the numbers). 2  Then for each number: subtract the Mean and square the result (the squared difference). 3  Then work out the average of those squared differences.
Vice versa, variance is standard deviation squared. To calculate standard deviation from variance, only take the square root. In our example, the variance was 200, therefore standard deviation is 14.14. For calculating standard deviation of a data set, first calculate the variance and then find the square root.