The median of 100 observations grouped in classes of equal width is 25 . If the median class interval is 20-30 and the number of observations less than 20 is 45 , then the frequency of median class is

Step-by-step solution

Median is given as M=l+ N 2 -F f C where l= lower limit of the median - class f= frequency of the median class N= total frequency F= cumulative frequency of the class just before the median class C= length of median class Now, given, M=25, N=100, F=45 , C=20-30=10, l=20 . By using formula, we have aligned & 25=20+ 50-45 f 10 & 25-20= 50 f 5= 50 f f=10 aligned