Let x be the class mark & y be the upper limit of a class-interval in a continuous frequency-distribution.
The lower limit of the class is:

Let m be the mid point and b be the upper limit of a class in a continuous frequency distribution. The lower limit of the class is

Let m be the mid-point and l be the upper class limit of a class in a continuous frequency ditribution. The lower class limit of the class is :

If m is the mid-point and l is the upper limit of a class in a continuous frequency distribution, then lower class limit of the class is

If m is the mid-point and l is the upper limit of a class in a continous frequency distribution, then lower class limit of the class is

The upper limit of class interval 20-30 is:

Upper limit of class interval 75-85 is

Consider the frequency distribution. The upper limit of median class is

Consider the following frequency distribution The lower limit of median class is