Question

The class marks of a distribution are $47,52,57,62,67,72,77$ Determine the class-size and the class limits (class intervals)

Answer 1

Class gaps are, $h=52-47=5$

$\Rightarrow$ If class marks are represented by $x_i$ then class intervals would be

$(x_1-\frac{x}{2},x_1+\frac{x}{2}),(x_2-\frac{x}{2},x_2+\frac{x}{2})$

$=(44.5,49.5),(49.5,54.4),(54.5,59.5),....$

with class size $x=5$.