Question

The runs scored by two teams $A$ and $B$ on the first $60$ balls in a cricket match are given below:
Represent the data of both the teams on the same graph by frequency polygons.

Answer 1

No. of balls	Class mark	Team A	Team B
0.5 - 6.5	3.5	2	5
6.5 - 12.5	9.5	1	6
12.5 - 18.5	15.5	8	2
18.5 - 24.5	21.5	9	10
24.5 - 30.5	27.5	4	5
30.5 - 36.5	33.5	5	6
36.5 - 42.5	39.5	6	3
42.5 - 48.5	45.5	10	4
48.5 - 54.5	51.5	6	8
54.5 - 60.5	57.5	2	10

Class intervals are not continuous.
$\therefore$ Because of gap of $1$, $0.5$ has to added and subtracted from upper and lower class limits.
Class mark $=\frac{upperclasslimit+lowerclasslimit}{2}$