The class mark of the class 90-120 is :
a. 90
b. 105
c. 115
d. 120

Solution:

In the class 90-120

Upper class=120

Lower class=90

We know that

Class mark = Upper class + Lower class/ 2

Substituting the values

Class mark = (120 + 90)/2

So we get

Class mark = 210/2

Class mark = 105

Therefore, the class mark is 105.

✦ Try This: The class mark of the class 80-100 is : a. 90, b. 160, c. 115, d. 120

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

NCERT Exemplar Class 9 Maths Exercise 14.1 Problem 1

The class mark of the class 90-120 is : a. 90, b. 105, c. 115, d. 120

Summary:

Class mark, in statistics, is the average of the upper limit and the lower limit of a class in a frequency distribution. The class mark of the class 90-120 is 105

☛ Related Questions:

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