In a frequency distribution table, the midpoints of the classes are 15, 20, 25 30, ….. respectively. The class having midpoint as 20 is

The range of the data 12, 25, 15, 18, 17, 20, 22, 26, 6, 16, 11, 8, 19, 10, 30, 20, 32 is

The class size of the classes 1–5, 6–10 is

In a frequency distribution table, the mid - point of a class is 10 and the class size of each class is 6; the lower limit of the class is

In a continuous frequency distribution table if the mid - point of a class is m and the upper class - boundary is u, then let us find out the lower class - boundary.