Question

Draw a pie diagram for the following data of expenditure pattern in a family :

Items	Food	Clothing	Rent	Education	Unforeseen	Medicine
Expenditure (in %)	40%	20%	10%	10%	15%	5%

Answer 1

Here, total expenditure = 100 % 

So, 

The central angle =\(\frac{component\,value}{100}\times360^\circ\)

Hence, 

the central angle for each activity will be calculated as follows

Item	Expenditure	Sector angle (degree)
Food	40%	40/100 x 360 = 144
Clothing	20%	20/100 x 360 = 72
Rent	10%	10/100 x 360 = 36
Education	10%	10/100 x 360 = 36
Unforeseen events	15%	15/100 x 360 = 54
Medicine	5%	5/100 x 360 = 18

Steps for construction of representation of data in pie chart 

Step 1: Draw the circle of appropriate radius. 

Step 2 : Choose a radius anywhere inside the circle. 

Step 3 : Now draw a sector of calculated component’s central angle. It is always preferable to choose component with largest central angle first and then continue in descending order of magnitude of their central angle. 

Step 4: After drawing sectors, shade them with different colours and label them as shown in the figure.