Question

For a frequency distribution, $\sum f_i{u}_i=-50,$ $n=100,$ $c=10$ and $\overline{x}=25,$ then assumed mean $A$= _____

• A. $30$
• B. $20$
• C. $40$
• D. $50$

Answer 1

The correct option is A $30$

$\Rightarrow$ We have, $\sum f_i{u}_i=-50,n=\sum f_i=100,c=h=10$ and $\overline{x}=25$

$\overline{x}=A+\frac{\sum f_i{u}_i}{\sum f_i}\times h$

$\Rightarrow$ $25=A+\frac{(-50)}{100}\times 10$

$\Rightarrow$ $25=A-5$

$\Rightarrow$ $A=25+5$

$\therefore$ $A=30$