Question

Answer the following questions in detail−

Calculate the arithmetic mean from the following

Marks	5	6	7	8	9
No. of students	5	12	15	10	8

Answer 1

Marks xi	No. of Students fi	xi fi
5	5	25
6	12	72
7	15	105
8	10	80
9	8	72
Total	50	354

$\overline{\mathrm{X}}=\frac{\sum x_i{f}_i}{\sum f_i}=\frac{354}{50}=7.08$