The given histogram and frequency polygon shows the ages of teachers in a school. Answer the following:

(i) What is the class size of each class?

(ii) What is the class whose class mark is 48?

(iii) What is the class whose frequency is maximum?

(iv) Construct a frequency table for the given distribution.

(i) From graph,

Class marks of two successive class are 36 and 30.

Class size = 36 - 30 = 6.

Hence, the class size of each class is 6.

(ii) Lower limit of class = Class mark - $\dfrac{\text{Class size}}{2}$

= 48 - $\dfrac{6}{2}$

= 48 - 3

= 45.

Upper limit of class = Class mark + $\dfrac{\text{Class size}}{2}$

= 48 + $\dfrac{6}{2}$

= 48 + 3

= 51.

Hence, class whose class mark is 48 is 45 - 51.

(iii) From table,

Class with class mark = 54 has greatest frequency.

Lower limit of class = Class mark - $\dfrac{\text{Class size}}{2}$

= 54 - $\dfrac{6}{2}$

= 54 - 3

= 51.

Upper limit of class = Class mark + $\dfrac{\text{Class size}}{2}$

= 54 + $\dfrac{6}{2}$

= 54 + 3

= 57.

Hence, class 51 - 57 has highest frequency.

(iv) Frequency table for the given distribution :