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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 ______.

#### Options

4

5

6

7

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#### Solution

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**.

**Explanation: **

Given data set is 268, 220, 368, 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 observations corresponding to class 310 – 330 are class 310, 310, 320, 319, 318, 316 that is 6 observations.

So, the frequency of the class 310 – 330 is 6.

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