# A grouped frequency table with class intervals of equal sizes using 250-270 (270 not included in this interval) as one of the class interval is constructed for the following data :

268, 220, 368, 258, 242, 310, 272, 342,

310, 290, 300, 320, 319, 304, 402, 318,

406, 292, 354, 278, 210, 240, 330, 316,

406, 215, 258, 236.

The frequency of the class 310-330 is:

a. 4

b. 5

c. 6

d. 7

**Solution:**

Let us arrange the data given in groups like 210-230, 230-250, 390-410

Class width will be 20

Let us arrange it in tabular form

Class Interval |
Tally marks |
Frequency |

210-230 |
||| |
3 |

230-250 |
||| |
3 |

250-270 |
||| |
3 |

270-290 |
|| |
2 |

290-310 |
|||| |
4 |

310-330 |
|||| | |
6 |

330-350 |
|| |
2 |

350-370 |
|| |
2 |

370-390 |
- |
0 |

390-410 |
||| |
3 |

Therefore, the frequency of the class 310-330 is 6.

**✦ Try This: **In the class intervals 10-20, 20-30, 30-40, 40-50 the number 40 is included in : a. 10-20, b. 30-40, c. all the intervals, d. 40-50

**☛ Also Check:** NCERT Solutions for Class 9 Maths Chapter 14

**NCERT Exemplar Class 9 Maths Exercise 14.1 Problem 8**

## A grouped frequency table with class intervals of equal sizes using 250-270 (270 not included in this interval) as one of the class interval is constructed for the following data :268, 220, 368, 258, 242, 310, 272, 342, 310, 290, 300, 320, 319, 304, 402, 318, 406, 292, 354, 278, 210, 240, 330, 316, 406, 215, 258, 236. The frequency of the class 310-330 is: a. 4, b. 5, c. 6, d. 7

**Summary:**

A grouped frequency table with class intervals of equal sizes using 250-270 (270 not included in this interval) as one of the class interval is constructed for the following data : 268, 220, 368, 258, 242, 310, 272, 342, 310, 290, 300, 320, 319, 304, 402, 318, 406, 292, 354, 278, 210, 240, 330, 316, 406, 215, 258, 236. The frequency of the class 310-330 is 6

**☛ Related Questions:**

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