Table of contents  
Introduction  
The Types of Pie Charts  
There are two types of pie charts  
Significance of Pie Charts  
Practice Question 
There are two approaches to constructing a pie chart from any given data:
(a) Degree Approach: The central angle in a circle represents 360°, so any part or segment in a pie chart is calculated as a proportion of 360°.
Conversion of degree approach to percentage approach:
If we convert the same pie chart into the degree format, we will be required to do the following conversions:
Total = 100%
Hence, 1% = 3.6°
Central = 10% = 36°
North = 20% = 72°
South = 25% = 90°
East = 15% = 54°
West =30% = 108°
(a) Normal Pie Chart
This displays the contribution of each component of the pie.
(b) Exploded Pie Chart
It is conventional to have multiple pie charts related to the same paragraph question to determine different aspects & drawing comparisons between the data.
Q.1. What is the percentage increase in sales in December 2017 as compared to the sales in December 2016?
(a) 38.46
(b) 22.22
(c) 50.00
(d) 28.57
Q.2. In which quarter of 2017 was the percentage increase in sales from the same quarter of 2016 the highest?
(a) Q4
(b) Q1
(c) Q2
(d) Q3
Sol: To easily solve the questions we can first represent the information given in piechart in a consolidated table to make it easier to read and understand.
As you can see in the above table there a few month’s sales are missing and we need to evaluate them first from the given information and then find the answers to above given question.
Now, it’s been given in the question that the months of April, May, June in 2016 forms an A.P. and so does the months of Quarter 4 of 2016, i.e. Oct, Nov, Dec.
Total sale in Quarter 2 = 150
Let ad, a, a+d be the three terms of A.P.
Hence, ad + a + a+d =150
Since, April sale is 40, i.e. ad = 40
Using that we can easily find the rest of the month sales values i.e. 50 and 60 respectively.
Similarly, using the above method we can find out the values for the month of Nov’16 and Dec’16. In this case, a wouldbe 120 and d = 20.
Thus, sales for these months are 120 and 140 respectively.
Now as you can see in the table, we have found out all missing monthly sales figure except for December’17 and August’17 which can be easily find out as
Total sales in Quarter 4 of 2017 = 500
And sales in Oct’17 and Nov’17 are 150 and 170 respectively.
Hence, the sale for December = 500 150  170 = 180
And similarly, Sale for August’17 = 220 – 60 – 70 = 90
Therefore, our table becomes,
Now we are in position to answer all the given questions using the above table.
Ans 1: Percentage increase in sales of Dec’17 as compared to Dec’16 =
Ans 2: We need to evaluate the quarter with the highest increase in sales in percentage terms.
The pie chart has gained prominence due to the following reasons:
Following is the cost analysis of a book “Guide to Digital Marketing”.
What is the central angle showing the cost of paper?
(a) 42.8°
(b) 32.6°
(c) 36.8°
(d) 57.6°
Sol: Percentage of paper cost in total cost  16%
We know that the sum of angles in pie chart is 100°
Hence, Required Angle = (16/100 × 360) = 57.6°
207 videos156 docs192 tests

1. What are the two types of pie charts? 
2. How are pie charts significant? 
3. How can pie charts be used in data analysis? 
4. How can pie charts be created and interpreted? 
5. What are some limitations of using pie charts? 
207 videos156 docs192 tests


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