Question

The following table shows the distribution of the heights of a group of factory workers :

$\begin{array}{cccccccc}\text{Ht. (cm):}& 150-155& 155-160& 160-165& 165-170& 170-175& 175-180& 180-185\\ \text{No. of workers}& 6& 12& 18& 20& 13& 8& 6\end{array}$

(i) Determine the cumulative frequencies.

(ii) Draw the 'less than' cumulative frequency curve on graph paper. Use 2 cm = 5 cm height on one axis and 2 cm = 10workers on the other.

Answer 1

We plot the points (155, 6), (160, 18), (165, 36), (170, 56), (175, 69),

(180, 77) and (185, 83) on the graph and join them in free hand to obtain an ogive.