A life insurance agent found the following data for distribution of ages of 100 policyholders. Calculate the median age, if policies are given only to persons having age 18years onwards but less than 60 year


Age (in years)



Number of policy holders



Below 20


Below 25


Below 30


Below 35


Below 40


Below 45


Below 50


Below 55


Below 60



2


6


24


45


78


89


92


98


100


the cumulative frequency can be calculated as:


Class intervals



Frequency



Cumulative frequency



15-20


20-25


25-30


30-35


35-40


40-45


45-50


50-55


55-60



2


4


18


21


33


11


3


6


2



2


6


24


45


78


89


92


98


100



As per the question,


N=100



Hence,


Median class = 35-45


Cumulative frequency = 100


Lower limit, l = 35


cf = 45


f = 33


h = 5


Now,


Median can be calculated as:




= 35 +


= 35.75


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