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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. - Mathematics

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प्रश्न

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.

उत्तर

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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अध्याय 15: Probability - Exercise 15.1 [पृष्ठ २८५]

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एनसीईआरटी Mathematics [English] Class 9
अध्याय 15 Probability
Exercise 15.1 | Q 13 | पृष्ठ २८५

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