How do you do random sampling?

You do random sampling is by getting a quadrat, for example, a 0.5m by 0.5m quadrat, then placing two 20m tape measures at right a right angle. You then need two bags containing the numbers 1 to 20, so the first student picks a number from the first bag, e.g. 8 then stands where that number falls on the tape measure, and the second student picks a number from the second bag e.g. 12 and stands at that point. Then a third student drops a quadrat at the point where the 8 and 12 meet, where they count the number of daisies in the first quadrat Now repeat the nine times, for 10 samples and calculate the total population of daisies using the equation. Then the students find the total population of daisies in the whole field using the total population size equation.