pie chart and its uses in economics activities

PIE CHARTS (OR GRAPHS) AND ITS USES IN ECONOMIC what is a pie chart: A pie chart or graph is a simple circle of any convenient size which is divided into sections or sectors, each of which is proportional to the quantity or value it represents.

other economic tools and table

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HOW IS A PIE CHART MEASURED?

The pie chart is usually measured either in percentage or in degrees with the aid of a mathematical device called a protractor. The entire circle is represented by 360o or 100% and each sector is measured in degrees with the aid of a protractor.

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    1. public enterprises
    2. private enterprises
    3. limited liability companies
    4. migration
    5. population
    6. market concept
    7. money market
    8. shares
    9. how companies raises funds for expansion
    10.  

    WEED AND THEIR BOTANICAL NAMES
    1. ENVIRONMENTAL FACTORS AFFECTING AGRICULTURAL PRODUCTION
    2. DISEASES
    3. 52. SOIL MICRO-ORGANISMS
    4. ORGANIC MANURING
    5. FARM YARD MANURE
    6. HUMUS
    7. COMPOST
    8. CROP ROTATION
    9. GRAZING AND OVER GRAZING
    10. IRRIGATION AND DRAINAGE

Methods of constructing a pie chart

Add up the total figure of the product or value under consideration.

Work out the percentage or degree the total which each component part represents.

Draw a circle of a convenient size.

 Divide the circle up into sector suspended by these angles calculated in step (ii) above using a protractor.

Write the percentage or degree of each sector by it.

Use key where the information cannot be written inside the circle to show what each sector represents.

ka typical bar chart or graph

HOW TO USE A PIE CHART TO SOLVE ECONOMIC DATA REPRESENTATION

Example 1 of the proper use the pie chart

Represent the information I table by means of pie chart, the value of the most important exports of Nigeria in 1980, both in percentages and in degrees.

Table 2.3: Value of the most important exports on Nigeria in 1980.

Export productValue in millions
Cocoa200
Groundnut140
Petroleum240
Coal50
Others90

Solution

  • Add up the total value of all the products, i.e. 200 + 140 + 240 + 50 + 90 = 720.
  • Arrange your workings or calculations as follows:
Export ProductValue in Millions (N)Workings in percentage (%)Workings in degree (0o) Angle of sector
Cocoa20200   
Groundnut140  
Petroleum240  
Coal50  
Others90  
TOTAL720  

 Using the values in degree, i.e. 100%, 70o, 120o, 25o and 45o, a pie chart in Fig. 2.2 is now drawn using a protractor.

Pie chart showing value of the most important exports of Nigeria in 1980.

Example 2

The table below shows the sectoral allocation of a country’s budget. Illustrate the data accurately with a pi chart. Show your workings clearly.

Table 2.4: Sectoral allocation of a country’s budget.

Sector                                     Amount (N Million)

Health                                     30

Education                    25

Housing                       15

Manufacturing            10ul

Agriculture                  20

Solution

SectorAmount (N Million) (Angle of Sector)Workings in degrees
Health30 
Education25 
Housing15 
Manufacturing10 
Agriculture20 
   

Total                100                  360o

  • Add up the total value of all the sectors, i.e. 30 + 25 + 15 + 10 + 20 = 100
  • Arrange your workings or calculations in the following manner only in degrees.
  • Using the values in degrees, i.e. 108o, 90o, 54o, 36o and 72o, a pie chart is now drawn.