First click to open the "Sample Size" calculation table. Then click on the input formula "=". Then enter the square value of the target population multiplied by the standard deviation, and then subtract the standard deviation multiplied by the square value of the error range from 1.

Sample size = target population 2 * standard deviation *( 1- standard deviation)/(error range) 2. Finally, press "Enter" to confirm and calculate the sample size. This is calculation. Sample size refers to the total number of sample elements extracted from the population, which is applied to statistics, mathematics, physics and other disciplines. Sample size is an important factor in selecting test statistics. According to the sampling distribution theory, under the condition of large samples, if the population is normally distributed, the sample statistics obey the normal distribution; If the population is non-normal, the sample statistics gradually obey the normal distribution. For example, the weight data of one hundred people are called samples, in which the sample size is 1 and the sample size is 100.