Question

The relative humidity (in %) of a certain city for a month of 30 days was as follows:-

98.1	98.6	99.2	90.3	86.5	95.3	92.9	96.3	94.2	95.1
89.2	92.3	97.1	93.5	92.7	95.1	97.2	93.3	95.2	97.3
96.2	92.1	84.9	90.2	95.7	98.3	97.3	96.1	92.1	89

(i) Construct a grouped frequency distribution table with classes

84 - 86, 86 - 88

(ii) Which month or season do you think this data is about?

(iii) What is the range of this data?

Answer 1

(i) A grouped frequency distribution table of class size 2 has to be constructed. The class intervals will be 84 − 86, 86 − 88, and 88 − 90…

By observing the data given above, the required table can be constructed as follows.

Relative humidity (in %)	Number of days (frequency)
84 − 86	1
86 − 88	1
88 − 90	2
90 − 92	2
92 − 94	7
94 − 96	6
96 − 98	7
98 − 100	4
Total	30

(ii) It can be observed that the relative humidity is high. Therefore, the data is about a month of rainy season.

(iii) Range of data = Maximum value − Minimum value

                           = 99.2 − 84.9 = 14.3