Question

Find the class marks of classes $10-25$ and $35-55$

Answer 1

Find the class mark of given class intervals

The average of the actual upper limit and actual lower limit for a given class is called the class mark.

Class mark of $10-25=\frac{\left(\mathrm{upper}\mathrm{limit}-\mathrm{lower}\mathrm{limit}\right)}{2}$

$=\frac{25+10}{2}$

$=\frac{35}{2}$

$=17.5$

So, class marks of class $10-25$ is $17.5$

Class mark of $35-55=\frac{\left(\mathrm{upper}\mathrm{limit}-\mathrm{lower}\mathrm{limit}\right)}{2}$

$=\frac{55+35}{2}$

$=\frac{90}{2}$

$=45$

So, class marks of class $35-55$ is $45$ .

Hence, the class mark of class $10-25$ is $17.5$ and class marks of class $35-55$ is $45$.