Interpreting Pie Charts

Mathematics

Quarter 4 – Module 4:

Constructing and Interpreting a Pie

Graph Based on a Given Set of Data

It is a type of graph that represents the data in the circular graph. The slices of pie show the relative size of the data, and it is a type of pictorial representation of data. A pie chart requires a list of categorical variables and numerical variables. Here, the term “pie” represents the whole, and the “slices” represent the parts of the whole. 

Pie Chart

Information or facts collected together for analysis.

Data

Teacher Ann, surveys her class on the basis favorite sport of her students:
Here are the data collected by Teacher Ann, 10 students say Baseball is their favorite sport, 10 says Basketball, 10 says Badminton, 5 says Sipa, 5 says Tennis. Teacher Ann wanted to make a Pie Chart for the data.

Step 1, Teacher Ann puts all the data into a table.

​Baseball	Basketball​	Badminton​	Sipa​	Tennis​
​10	10​	10​	5​	5​

Step 2. Teacher Ann, add all the values in the table to get the total respondents.
Baseball - 10
Basketball - 10
Badminton - 10
Sipa - 5
Tennis - 5
Total - 40 There are 40 students who responded in the survey.

Step 3. She divide each value by the total and multiply by 100 to get the percentage.

​Baseball	Basketball​	Badminton​	Sipa​	Tennis​
​(10 ÷ 40) =0.25 × 100 = 25%	​(10 ÷ 40) =25 × 100 = 25%	(10 ÷ 40) =25 × 100 = 25%​	(5 ÷ 40) =0.125 × 100 = 12.5%​	(5 ÷ 40) =0.125 × 100 = 12.5%

Step 4. Teacher Ann, wants to know the "degrees" for each "pie sector", she took the full circle of 360° and follows the calculations below:

angle of each component = percentage of each component × 360°

​Baseball	Basketball​	Badminton​	Sipa ​	Tennis​
25% × 360° = 90°	25% × 360° = 90°	25%​ × 360° = 90°	12.5% × 360°= 45°	12.5% ×​ 360° = 45°

Step 5. Teacher Ann, draws the pie chart using a compass and draws the pie sections using a protractor accordingly.

How to draw sections of a Pie Graph.

See video: https://youtu.be/FXFSthJhkmk

Points to remember!

Step 1. Arrange data in a table.
Step 2. Add all values for total.
Step 3. Each value divided by total multiply by 100 to get percent.
Step 4. Multiply each percent by 360°.
Step 5. Draw pie chart.
Step 6. Use Calculator and Protractor to make a Pie chart.

Try These!

I.
A. Read and Study the data carefully. Construct a pie graph out of it. Copy and answer on your answer sheet.


Mrs. Gonzalez spends her monthly income this way.

°

Expenditures​	Amount​	Percent​	Degrees​
​Food	​₧ 4,500.00	​37%	​135°
Education​	​₧ 3,000.00	25%​	​90°
Monthly Bills​	​₧ 1,500.00	12.5%​	45°​
Transportation	₧ 1,800.00	15%	54°
Savings	₧ 1,200.00	10%	36°
Total	₧ 12,000.00	100%	360°

B. Use the data in the pie graph that you had constructed to answer the following questions.

1. What percent of the monthly income does Mrs. Gonzales spend on education?
2. In which categories does she spend the greatest part of her income?
3. How much does she spend for her transportation?
4. How much more does she spend on paying for food than monthly bills?
5. How much does she save monthly?

​Ice Cream Flavor	Number of Learners​
​Rocky Road	10​
​Double Dutch	4​
​Strawberry	10​
​Vanilla	4​
​Chocolate	12​
​TOTAL	40​

Construct a pie graph/chart using the data in the table.

​​II.
The table below shows the percentage of learners who like the given flavors of ice cream.