The blood groups of 30 students of Class VIII are recorded 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. Which is the most common, and which is the rarest, blood group among these students?
Solution:
Given that the blood group of 30 students of class VIII and we have to find the most common blood group and the rarest blood group.
By drawing a frequency distribution table, we can check which group is occurring most and which group is occurring least time.
Let us sort the data using a table to make the data more easily understandable and its important features visible.
This table is known as the frequency distribution table.
‘Frequency’ of a particular data refers to the number of times the data value occurs. In our case, frequency refers to the number of students having the same blood group.
The blood group of 30 students of Class VIII can be shown as follows:
BLOOD GROUP |
NUMBER OF STUDENTS (frequency) |
A B O AB |
9 6 12 3 |
Total |
30 |
Now, we can see easily from the table, that:
- The most common (most frequently occurring) blood group is ‘O’.
- The rarest blood group (least frequently occurring) is ‘AB.’
Thus, the most common blood group is ‘O’ and the rarest blood group is ‘AB.’
☛ Check: NCERT Solutions for Class 9 Maths Chapter 14
Video Solution:
The blood groups of 30 students of Class VIII are recorded 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. Which is the most common, and which is the rarest, blood group among these students?
NCERT Solutions for Class 9 Maths Chapter 14 Exercise 14.2 Question 1
Summary:
It is given that blood groups of 30 students of Class VIII are recorded 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. We have found that the most common blood group is ‘O’ and the rarest blood group is AB using frequency distribution table.
☛ Related Questions:
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