Question

Calculate arithmetic mean with the help of following data. Use step deviation method.

Wages (in Rs.)

20

25

30

40

42

50

No. of students

4

6

10

5

5

10

Answer 1

$$20\times4=80$$

$$25\times6=150$$

$$30\times10=300$$

$$40\times5=200$$

$$42\times5=210$$

$$50\times10=500$$

$$80+150+300+200+210+500=1440$$

$$4+6+10+5+5+10=40$$

$$\frac{1440}{40}=36$$