Find the frequency of 40 in the following set of data.
10, 40, 80, 100, 60, 40, 30, 40, 20, 40.
4
To find the frequency of an observation, we have to count how many times the observation occurs in the data.
In the given set of data, the value '40' occurs 4 times.
Thus, the frequency of 40 is 4.