Question

The prices of different articles and demand for them is shown in the following frequency distribution table. Find the median of the prices.

Price (Rupees)	20 less than	20 - 40	40 - 60	60 - 80	80 - 100
No. of articles	140	100	80	60	20

Answer 1

Class (Prices in Rupees)	Frequency (Number of articles) fi	Cumulaive frequency less than the upper limit
0 - 20	140	140
20 - 40 (Median Class)	100	240
40 - 60	80	320
60 - 80	60	380
80 - 100	20	400
	N = 400

From the above table, we get
L (Lower class limit of the median class) = 20
N (Sum of frequencies) = 400
h (Class interval of the median class) = 20
f (Frequency of the median class) = 100
cf (Cumulative frequency of the class preceding the median class) = 140
Now, Median = $L+\left(\frac{{\displaystyle \frac{N}{2}-cf}}{f}\right)\times h$
​$=20+\left(\frac{{\displaystyle \frac{400}{2}-140}}{100}\right)\times 20$
= 20 + 12
= Rs 32
Hence, the median of the prices is Rs 32.