Consider the data :
Class | 65-85 | 85-105 | 105-125 | 125-145 | 145-165 | 165-185 | 185-205 |
Frequency | 4 | 5 | 13 | 20 | 14 | 7 | 4 |
The difference of the upper limit of the median class and the lower limit of the modal class is
(A) 0 (B) 19 (C) 20 (D) 38
Answer. [C]
Solution. Frequency distribution: It tells how frequencies are distributed overvalues in a frequency distribution. However mostly we use frequency distribution to summarize categorical variables.
Class | Frequency | Cumulative Frequency |
65-85 | 4 | 4 |
85-105 | 5 | (4+5=9) |
105-125 | 13 | (9+13=22) |
125-145 | 20 | (22+20=42) |
145-165 | 14 | (42+14=56) |
165-185 | 7 | (56+7=63) |
185-205 | 4 | (63+4=67) |
N = 67 |
Median class = 125 – 145
upper limit of median = 145
The class with maximum frequency is modal class which is 125 – 145
lower limit of modal class = 125
Difference of the upper limit of median and lower limit of modal = 145 – 125 = 20