Let m be the mid-point and l be the upper class limit of a class in a continuous frequency distribution. The lower class limit of the class is:
a. 2m + l
b. 2m - l
c. m - l
d. m - 2l

Solution:

Consider x and y as the lower and upper limit of a continuous frequency distribution

It is given that

Midpoint of a class = (x + y)/2 = m

By cross multiplication

x + y = 2m

Let us take y as l

x + l = 2m

x = 2m - l

Therefore, the lower class limit of the class is 2m - l.

✦ Try This: The width of each of five continuous classes in a frequency distribution is 3 and the lower class-limit of the lowest class is 9. The upper class-limit of the highest class is:

☛ Also Check: NCERT Solutions for Class 9 Maths Chapter 14

NCERT Exemplar Class 9 Maths Exercise 14.1 Problem 5

Let m be the mid-point and l be the upper class limit of a class in a continuous frequency distribution. The lower class limit of the class is : a. 2m + l, b. 2m - l, c. m - l, d. m - 2l

Summary:

Let m be the mid-point and l be the upper class limit of a class in a continuous frequency distribution. The lower class limit of the class is 2m - l

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