#### In a class of 90 students, the marks obtained in a weekly test were as under:

Marks | 16-20 | 21-25 | 26-30 | 31-25 | 36-40 | 41-45 | 46-50 |

No. of students | 4 | 12 | 18 | 26 | 14 | 10 | 6 |

**Solution:**

Marks | Classes after adjustment | Class Mark | No. of students (f) |

16-20 | 15.5-20.5 | 18.0 | 4 |

21-25 | 20.5-25.5 | 23.0 | 12 |

26-30 | 25.5-30.5 | 28.0 | 18 |

31-35 | 30.5-35.5 | 33.0 | 26 |

36-40 | 35.5-40.5 | 38.0 | 14 |

41-45 | 40.5-45.5 | 43.0 | 10 |

46-50 | 45.5-50.5 | 48.0 | 6 |

Represent marks on x-axis and frequency on y-axis :

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