The following table gives weekly wages in rupees of workers in a certain commercial organization. The frequency of class 49-52 is missing. It is known that the mean of the frequency distribution is 47.2. Find the missing frequency.

Explanation

we have
`bar X=42.7,A=47.5`and `h=3`


`bar X=A+h(1/Nsumf_ih_i`


`47.2=47.5+3X((f-66)/(176+f))`


`-0.3=3X((f-66)/(176+f)`
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