Question

The following data gives the weights of 30 persons (in kg)
70.0,69.4,49.4,64.5,59.4,72.4,47.5,48.8,62.3,64.2,66.8,70.3,71.3,56.3,52.7,66.6,59.9,64.7,44.6,60.3,50.3,54.3,62.3,56.3,45.0,45.7,49.8,60.5,67.8,50.1,
(i) Construct a frequency distribution such that the last class is 72-76.
(ii) State the upper class limits of last three class intervals.
(iii) State the maximum weight that can be included in the fourth class interval.
(iv) State the class mark of each of the classes.
(v) Find the range of the given weights.
(vi) If 60kg is the weight of a person then in which class interval, it will be taken.

Answer 1

Minimum weight = 44.6
Maximum weight = 72.4
and it is given that last class interval is 72-76.
(i) So, frequency distribution is

(ii) Upper limits of last three class intervals are 68,72,76.
(iii) The weights in 4th class interval 56-60 are 59.4,56.3,59.9,56.3
`therefore " Maximum weight in this class interval" = 59.9 kg`
(iv) Class marks of each class are `(44+48)/(2),(48+52)/(2),(52+56)/(2),(56+60)/(2)` etc.
i.e., 46,50,54,58,62,66,70,74
(v) Range = maximum weight-minimum weight
= 72.4-44.6 = 27.8
(vi) Weight 60 kg is taken in class 60-64.