Sum

Following data gives the age in years and marks obtained by 30 students in an intelligence test.

Age |
16 | 17 | 22 | 19 | 21 | 16 |

Marks |
16 | 19 | 39 | 50 | 48 | 41 |

Age |
21 | 20 | 20 | 23 | 22 | 19 |

Marks |
59 | 44 | 42 | 62 | 37 | 67 |

Age |
23 | 20 | 22 | 22 | 23 | 22 |

Marks |
45 | 57 | 35 | 37 | 38 | 56 |

Age |
17 | 18 | 16 | 21 | 19 | 20 |

Marks |
54 | 61 | 47 | 67 | 49 | 56 |

Age |
17 | 18 | 23 | 21 | 20 | 16 |

Marks |
51 | 42 | 65 | 56 | 52 | 48 |

Prepare a bivariate frequency distribution by taking class intervals 16 – 18, 18 – 20, … etc. for age and 10 – 20, 20 – 30, ... etc. for marks. Find marginal frequency distributions.

Advertisement Remove all ads

#### Solution

Let

X = Age in years

Y = Marks

Bivariate frequency table can be prepared by taking class intervals 16 – 18, 18 – 20, … etc for X and 10 – 20, 20 – 30, … etc for Y.

Bivariate frequency distribution is as follows:

Marks (Y)/Age in years (X) |
16 – 18 |
18 – 20 |
20 – 22 |
22 – 24 |
Total (f_{y}) |

10 – 20 |
II (2) | – | – | – | 2 |

20 – 30 |
– | – | – | – | 0 |

30 – 40 |
– | – | – | IIII (5) | 5 |

40 – 50 |
III (3) | II (2) | III (3) | I (1) | 9 |

50 – 60 |
II (2) | I (1) | IIII (5) | I (1) | 9 |

60 – 70 |
– | II (2) | I (1) | II (2) | 5 |

Total (f_{x}) |
7 | 5 | 9 | 9 | 30 |

Marginal frequency distribution of X:

X |
16 – 18 | 18 – 20 | 20 – 22 | 22 – 24 | Total |

Frequency |
7 | 5 | 9 | 9 | 30 |

Marginal frequency distribution of Y:

Y |
10 – 20 | 20 – 30 | 30 – 40 | 40 – 50 | 50 – 60 | 60 – 70 | Total |

Frequency |
2 | 0 | 5 | 9 | 9 | 5 | 30 |

Concept: Classification and Tabulation of Bivariate Data - Marginal Frequency Distributions

Is there an error in this question or solution?

Advertisement Remove all ads

#### APPEARS IN

Advertisement Remove all ads

Advertisement Remove all ads