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

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:

• A grouped frequency distribution table with classes of equal sizes using 63-72 (72 included) as one . . . .
• To draw a histogram to represent the following frequency distribution : Class Interval 5-10 10-15 15 . . . .
• The mean of five numbers is 30. If one number is excluded, their mean becomes 28. The excluded numbe . . . .