Question

The upper class limit of $24 - 30$ is?
A. $24$
B. $30$
C. $24{\text{ or 30}}$
D. none of these

Answer 1

Hint:
If we are given the class interval $a - b$ then we can say that $a$ is the lower limit and $b$ is the upper limit and the difference between them is called the class size of that class interval.

Complete step by step solution:
So basically the lower and the upper class limit are the two types of the class limits given for each class interval. The lower class limit is the small value that goes into that class interval and the upper class interval as the largest value for that same class interval. As we have defined the class limit now we must have the knowledge of what is a class mark. So class mark is the midpoint of the given class interval. This is found by taking the average of both the class limit which is the upper and the lower class limit. The value obtained is called the class mark for that class interval. We can say that
Class mark$ = $$\dfrac{{{\text{lower class limit}} + {\text{upper class limit}}}}{2}$
Let us understand it by taking a simple example:
If we have the examination marks represented in which we see that for the marks lying between $50 - 100$ we have $10$ students
Here we can say that for the class interval $50 - 100,50$ is the lower limit and $100$ is the upper class limit.
Hence we can calculate the class mark by taking their average as $\dfrac{{50 + 100}}{2} = 75$
And frequency is $10$
So, here as we are given the class interval $24 - 30$ we can say that $24$ is the lower class limit and $30$ is the upper class limit.

Hence we can say that our option B is the correct one.

Note:
In these types of questions we must know the definition of what the upper class limit and the lower class limit are. Here we must have an idea of the class interval, class marks, frequency and other terms used in the statistics.