# Plz slove all the question 15 to 23 plz slove allthe question not one question

18) Average marks = total marks / no. of students

52 = Total marks / 30

Total marks = 1560.

Average marks of top 6 students = total marks of top 6 students / 6

31 = total marks of top 6 students / 6

total marks of top 6 students = 186.

Marks of rest of (24) students = marks of 30 students - marks of top 6 students / 24

Marks of rest of (24) students = 1560 - 186 / 24

Marks of rest of (24) students = 1374 / 24 = 57.25

19)

Class interval | mid point (X) | Frequency (f) | fX |

0-10 | 5 | 5 | 25 |

10-20 | 15 | x | 15x |

20-30 | 25 | 15 | 375 |

30-40 | 35 | 16 | 560 |

40-50 | 45 | 6 | 270 |

Total | 42 + x | 1230 + 15f |

Arithmetic mean = ∑ fx / ∑ f

27 = 1230 + 15x / 42 + x

1230 + 15 x = 42 + x (27)

1230 + 15 x = 1134 + 27 x

1230-1134 = 27 x - 15 x

96= 12 x

x = 8

kindly do not pile up questions in single thread use different threads for different questions.

Regards

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