Q7 of 25 Page 346

The distribution below gives the weights of 30 students of a class. Find the median weight of the students.


For median:


We have, total frequency, N = 30


N/2 = 30/2 = 15


Observe, cf = 19 is just greater than 15.


Thus, median class = 55-60


Median is given by



Where,


L = Lower class limit of median class = 55


N/2 = 15


cf = cumulative frequency of the class preceding median class = 13


f = frequency of the median class = 6


h = class interval of the median class = 5


Substituting these values in the formula of median, we get



⇒


⇒ Median = 55 + 1.67


⇒ Median = 56.67


Thus, the median is 56.67 kg.


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