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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.

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#### 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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