Question

Given below are Marks obtained by 20 students in Math out of 25.
21, 23, 19, 17, 12, 15, 15, 17, 17, 19, 23, 23, 21, 23, 25, 25, 21, 19, 19, 19.
Prepare a frequency distribution table for the given data.

Answer 1

Hint: Now to create a frequency table first we will list all the marks and make a column for the same. Now the number of times a particular number appears in the given list is called the frequency. Hence we will create another column of frequency and note down the value of frequency corresponding to marks in the table.

Complete step-by-step answer:
Now we are given the marks of 20 students which are as follows.
21, 23, 19, 17, 12, 15, 15, 17, 17, 19, 23, 23, 21, 23, 25, 25, 21, 19, 19, 19.
Now let us first list all the marks that appear in the given data.
21, 23, 19, 17, 12, 15, 25.
Now let us arrange the list in ascending order hence we get.
12, 15, 17, 19, 21, 23, 25.
Now we know that frequency is nothing but the number of times the number appears on the given list.
For example consider the list 1, 2, 3, 1, 5, 4, 6, 5, 1, 2, 3, 4.
Here 1 appears 3 times hence the frequency corresponding with 1 is 3.
Now let us create a table of all the marks and the corresponding frequency.

Marks	Frequency (No of students)
12	1
15	2
17	3
19	5
21	3
23	4
25	2

Hence we have the frequency distribution of the given data.

Note: Now note that the frequencies are nothing but the number of students with the corresponding marks. Hence the sum of all the frequencies is nothing but the total number of students. Hence it is always better to cross check if the sum of all frequencies is the total number of data, in this case the total number of students.