Measurement of Range in Continuous Series

Range= Upper Limit of the Highest Class Interval - Lower Limit of the Lowest Class Interval

Method 2 : Range is the difference of the mid value of the highest class and that of the lowest class.

Range= Mid-Value of the Highest Class Interval - Mid-Value of the Lowest Class Interval

Example : For the following data calculate the range.

X

f

0-10

10

10-20

15

20-30

11

30-40

17

40-50

13

Solution :

Method 2: Range = Mid-Value of the Highest Class Interval - Mid-Value of the Lowest Class Interval

Range = 45 5= 40

Q) In finding the mid value we should use ' + ' sign or ' - ' sign ?

The solution you have presented is wrong as (50-40)/2 = 45 as it should be (50+40)/2 = 45.

it is for both the cases

case 1 :- MID VALUE OF HIGHEST CLASS INTERVAL

case 2 :- MID VALUE OF LOWEST CLASS INTERVAL