The table below shows the salaries of 280 persons.


Calculate the median and mode of the data.


First, we construct a cumulative frequency table


N/2 = 280/2 = 140


(i) Here, median class is 10 - 15, because 140 lies in it.


Lower limit(l) = 10,


Frequency(f) = 133


Cumulative frequency (fc) = 49 and class width (h) = 5






= 10 + 3.421


= Rs.13.421 (in thousand)


= 13.421× 1000


= Rs.13421


(ii) Here, the highest frequency is 133, which lies in the interval 10 - 15, called modal class.


Lower limit(l) = 10, class width(h) = 5,


fm = 133,


f1 = 49 and


f2 = 63






= 10 + 2.727


= Rs.12.727 (in thousand)


= 12.727 × 1000 = Rs.12727


Hence, the median and modal salary are Rs.13421 and Rs12727, respectively.


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