Question

In the class intervals 10-20, 20-30, the number 20 is included in:

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 grouped frequency distribution table with classes of equal sizes using 63-72 (72 included) as one of the class is constructed for the following data: 30, 32, 45, 54, 74, 78, 108, 112, 66, 76, 88, 40, 14, 20, 15, 35, 44, 66, 75, 84, 95, 96, 102, 110, 88, 74, 112, 14, 34, 44. The number of classes in the distribution will be:

30 children were asked about the number of hours they watched TV programmes last week. The results are recorded as under: Number of hours 0-5, 5-10, 10-15, 15-20; Frequency 8, 16, 4, 2. Can we say that the number of children who watched TV for 10 or more hours a week is 22? Justify your answer.