The blood groups of 30 students of class IX 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, A student is selected at random from the class from blood donation. Find the probability that the blood group of the student chosen is A.

Given:

The blood groups of 30 students of class IX.

A student is selected at random from the class from blood donation.

To do:

We have to find the probability that the blood group of the student chosen is A.

Solution:

Total number of students $=30$

Number of students whose blood group is A $=9$

We know that,

Probability of an event=$ \frac{Number \ of \ favourable \ outcomes}{Total \ number \ of \ outcomes}$

Therefore,

Probability that the blood group of the student chosen is A $=\frac{9}{30}$

$=0.3$

This implies,

The probability that the blood group of the student chosen is A is $0.3$.

Related Articles 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, ORepresent 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.
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?
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