Q5 of 26 Page 14

Let l be the lower-class limit of a class-interval in a frequency distribution and m be the mid-point of the class. Then, find the upper-class limit f.

To Find: Upper-Class limit

Given:


Lower class limit = l


Mid-point = m


Concept Used: Mid-Point is the average of the lower limit and upper limit.


Explanation:


We know that,



Cross-multiplying, we get,


l + u = 2m


u = 2m – l


Hence, the upper limit is (2m – l).


More from this chapter

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3

In a frequency distribution, the mid-value of a class is 10, and the width of the class is 6. Find the lower limit of the class.

 4

Write the class mark of the class 130-150.

 6

In a group of 10 students, marks obtained in a subject are as follows: 23, 22, 45, 38, 49, 23, 45, 10, 45, 39. Find the following:
(i) Mean marks of class
(ii) Median marks of class
(iii) Modal marks of class

 7

The blood groups of 30 students of class VIII are recoded as follows:

A, B, O, O, AB, O, A, O, B, A, O, B, A, O, O, A, AB, O, A, A, O, O, AB, B, A, O, B, A, B, O


Represent this data in the form of a frequency distribution table. Find out which is the most common and which is the rarest blood group among these students.