Question

Following data gives the break up of the cost of production of a book:

Printing	Paper	Binding charges	Advertisement	Royalty	Miscellaneous
30%	15%	15%	20%	10%	15%

Draw a pie- diagram depicting the above information.

Answer 1

We know:
Central angle of a component = (component value/sum of component values x 360)
Here, total expenditures = 105%
Thus, the central angle for each component can be calculated as follows:

 

Item	Expenditure (in %)	Sector angle
Printing	30	30/105 x  360 = 102.9
Paper	15	15/105 x 360 = 51.4
Binding charges	15	15/105 x 360 = 51.4
Advertisement	20	20/105 x 360 = 68.6
Royalty	10	10/105 x 360 = 34.3
Miscellaneous	15	15/105 x 360 = 51.4

Total : 105%
Now, the pie chat representing the given data can be constructed by following the steps below:
Step 1 : Draw circle of an appropriate radius.
Step 2 : Draw a vertical radius of the circle drawn in step 1.
Step 3 : Choose the largest central angle. Here the largest central angle is 102.9^o. Draw a sector with the central angle 102.9^o in such a way that one of its radii coincides with the radius drawn in step 2 and another radius is in its counter clockwise direction.
Step 4 : Construct other sectors representing the other items in the clockwise sense in descending order of magnitudes of their central angles.
​Step 5 : Shade the sectors with different colours and label them, as shown as in figure below.​​