Suppose there are 50 students in a class and you want to select 10 students using the systematic sampling technique. The first step is to determine the width of the interval (50/10 = 5). This means that from every five you need to select one element. Using the SRS technique, from the first interval (1–5 elements), select one of the elements. Suppose you selected the third element. From the rest of the intervals you would select every third element.