# Lesson Notes By Weeks and Term - Senior Secondary 1

Population density

Term: 2nd Term

Week: 10

Class: Senior Secondary School 1

Age: 15 years

Duration: 40 minutes of 2 periods each

Date:

Subject:      Economics

Topic:-       Population Density

SPECIFIC OBJECTIVES: At the end of the lesson, pupils should be able to

1. Discuss the four basic structures/distributions of population
2. Calculate the dependency ratio

INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers, demonstration, videos from source

INSTRUCTIONAL MATERIALS: Videos, loud speaker, textbook, pictures

INSTRUCTIONAL PROCEDURES

PERIOD 1-2

 PRESENTATION TEACHER’S ACTIVITY STUDENT’S ACTIVITY STEP 1 INTRODUCTION The teacher reviews the previous lesson on population census Students pay attention STEP 2 EXPLANATION She explains the four different distributions of population with their effects and implications Students pay attention and participates STEP 3 DEMONSTRATION She further shows the learners how to calculate the dependency ratio. Students pay attention and participate STEP 4 NOTE TAKING The teacher writes a summarized note on the board The students copy the note in their books

NOTE

POPULATION DENSITY

Population is distributed or structured into four: Geographical Distribution,

Age Distribution, Sex distribution and Occupational Distribution.

1. Geographical Distribution

This is the breakdown of the population of a country into different

geographical zones.  It shows the number of people that are living in the

various parts of the country.

FACTORS AFFECTING GEOGRAPHICAL DISTRIBUTION OF POPULATION

1. Concentration of Industries: People generally tend to move towards areas where industries, factories, or offices are situated. This is in hope of seeking employment in such places.
2. Commercial Centres:Commercial activities going on in certain areas encourage population growth there. This is one reason why urban areas like Lagos, Port-Harcourt, Onitsha, Aba, etc are heavily populated.
3. Topography and Fertility of Soil: Since farming is a major occupation of people of West Africa, farmers tend to settle in areas with good topography and where the soil is fertile for agricultural purposes.
4. Climatic and Weather Condition: Some areas with friendly climate tend to be densely populated than areas with harsh climate.

1. Age Distribution

This refers to how the total population is spread among the various age

groups. We shall group the ages into three:

0-17 years    ⇒   Dependent Population

18-60 years   ⇒   Working Population or Labour force

60 and above   ⇒   Dependent Population

IMPLICATIONS OF AGE DISTRIBUTION

1. Dependent Population: This is made up of children who are below 18years and the aged who are above 60 years.  The implication of this is that if the larger number of a country falls within these age groups, it will impose a lot of burden on the working population.
2. Working Population: This constitutes the strength of the nation. It is active and productive. The implication of this also is that if the nation has a large working population, the nation will be productive and economic development would not be far-fetched.

DEPENDENCY RATIO

This is the ratio of the dependent population to the working population.

Formula = Dependent population : Working population

Example: Use the data in the table below to answer the questions that follow.

 Age Group No. of Persons in Thousands 1955 1960 0 – 18 150 143 18 – 45 51 107 46 – 60 29 33 Above 60 15 17
1. Calculate the ratio of the dependant population to the working population in 1955
2. Calculate the ratio of the dependant population to the working population in 1960

Solution:

1. Ratio of the Dependant in 1955

Dependant = 150 + 15 = 165

Working Population  = 51 + 29  =    80

= 165 : 80

= 33 : 16

1. Sex Distribution

This is the distribution of population into male and female. Sex distribution

is necessary because it guides the government in policies formulation. For

example: the larger number of female in the country, will indicate that, there

is need to produce more female-related goods like maternity centres. It will

also show that there is likely going to be increase in birth rate.

1. Occupational Distribution

This is the distribution of population according to various jobs and

occupation such as engineers, teachers, farmers, etc.  Occupation is

usually divided into three:

1. Primary Occupation/Extractive Occupation
2. Secondary Occupation/manufacturing
3. Tertiary occupation/Services

EVALUATION:    1. Discuss the four methods of population distribution

1. How is the dependency ratio calculated?
2. Attempt the ratio of the dependant population to the working population in 1960.

CLASSWORK: As in evaluation

CONCLUSION: The teacher commends the students positively