Calculate the arithmetic mean of the following frequency distribuition using the step-deciation method

Explanation

Here , h=50 . Let the asssumed mean be A=125
For calculating the mean , We prepare the table given as follows :


Thus we have
`A=125, h=50, Sigmaf_i=180 and Sigma(f_iu_i)=85`
Mean `barx=A+{hxx(Sigma(f_iu_i))/(Sigmaf_i)}`
`=125+{50xx(85)/(180)}=125+23.61=148.61`
Hence , the mean of the following is 148.61