Question

The number of CFL bulbs and LED bulbs by a seller every month from March to August are given below. Draw by vertical double bar graph.

Month	CFL Bulbs	LED Bulbs
March	70	75
April	35	30
May	65	75
June	90	100
July	22	35
August	50	50

Answer 1

Steps in drawing a Double bar graph: 

1. Draw X-axis (horizontal line) and Y – axis (vertical line) on the graph paper and mark their intersection point as ‘O’. 

2. Take ‘months’ on X – axis. 

3. Take number of CFL and LED bulbs on Y ~ axis. 

4. Take an appropriate scale on Y axis so that number of both the bulbs can be shown easily. Here the maximum value to be plotted on Y – axis as 100, so let us take 1 cm =10 bulbs on Y – axis. 

5. Find the length of each bar by dividing the value by 10 (as scale is 1 cm = 10 bulbs). 

Eg: 

Length of bar represents 70 CFL bulbs = 70/10 = 7cm

Length of bar represents 75 LED bulbs = 75/10 = 7.7 cm