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Question
| Blood Group | Number of Students |
| A | 9 |
| B | 6 |
| AB | 3 |
| O | 12 |
| Total | 30 |
The above frequency distribution table represents the blood groups of 30 students of a class. Use this table to determine the probability that a student of this class, selected at random, has blood group AB.
Solution
Number of students having blood group AB = 3
Total number of students = 30
Hence, required probability, `P = 3/30 = 1/10`
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