NCERT Solutions Exploring Society: India and Beyond Chapter 13 Chapter opener — The Big Questions
Book page 167 Updated on2026-09-05
Q1.
What is demography?
Answer
Demography is the study of the composition of a human population — its age groups, sexes, levels of education, occupations and religions — and of how that composition changes over time. The changes come from three things: births, deaths, and the movement of people within and across countries.
Notice that demography is not simply counting heads. The chapter shows it as having three parts (Fig. 6.2):
Size — how many people there are.
Structure and composition — how those people are made up by age, gender, education and so on.
Pattern and trend — which way the numbers are moving, and how fast.
Why the second and third parts matter as much as the first: two countries can have exactly the same number of people and need completely different things. If most of them are children, the country needs schools; if most are elderly, it needs hospitals and geriatric care; if most are of working age, it needs jobs. The chapter puts it plainly — “if a place has many young children, more schools are needed; if the proportion of the elderly in a population is higher, more facilities for healthcare are required.” A head count alone would tell a government nothing about what to build.
This is why governments collect the information: to plan infrastructure such as schools, hospitals, roads and housing, and municipal services like water, energy and waste management. Businesses use the same information to judge who their customers are, by age, gender and income, and to design products that match people’s needs. In India the instrument for collecting it is the census, conducted generally every 10 years.
Q2.
What are some important concepts of demography?
Answer
The chapter builds the subject out of four key indicators (Fig. 6.7) and then adds the ideas that are derived from them.
Indicator
What it measures
Unit
India’s figure in the chapter
Birth rate
Live human births during a year
per 1,000 population
High birth rate → faster growth
Fertility rate
Average number of children a woman would have in her lifetime
children per woman
5.7 (1950) → 1.9 (2025)
Death or mortality rate
Deaths in a population during a year
per 1,000 people
Child mortality 271 (1950) → 28 (2023) per 1,000
Migration
Movement of people from one place to another, within or outside the country
number of people moving
Grew Delhi, Mumbai, Bengaluru
Birth rate and fertility rate are not the same thing: the birth rate is counted per 1,000 people of the whole population, so it depends partly on how many women of child-bearing age happen to be in that population. The fertility rate is counted per woman, so it measures family size directly. A country can have a falling fertility rate and still, for a while, a high birth rate — simply because it has an unusually large number of young women. The chapter says the two “are closely linked”: when fertility falls, the birth rate follows.
The concepts built on top of these four are:
Replacement level fertility — 2.1. The number of children needed to replace the parents in the population. Above 2.1 a population is likely to grow; below it, it may shrink over time.
Life expectancy at birth. The average number of years a newborn is expected to live if conditions stay as they are today. In India it has risen from 30 years at Independence to 70 in 2024.
Sex ratio. The number of females per 1,000 males — 943 in Census 2011, up from 933 in 2001.
Census. The process of collecting, compiling, analysing and disseminating demographic, economic and social information about everyone in a country at a specific time.
Population pyramid (population structure diagram). A graph of the population by age group and gender, from which the whole story of a country’s past births and deaths can be read.
Demographic transition. The three-stage path along which birth and death rates fall as a country develops.
Demographic dividend and the youth bulge. The growth potential created by a large young, working-age population.
Median age. The age that divides a population in half — 28 for India, 50 for Japan (Fig. 6.17).
Q3.
How has the population of India and the world changed over time?
Answer
Both have grown enormously, but both are now growing more slowly every decade. Read the two graphs together.
The world (Fig. 6.4) grew from 2.5 billion in 1951 to 8.2 billion in 2025 — that is
8.2 ÷ 2.5 = 3.28 times as many people in 74 years
The United Nations expects 9.7 billion by 2050, a peak of 10.3 billion in the mid-2080s, and a gradual decline after that as birth rates fall. Fig. 6.4 already shows the flattening: 10.2 billion in both 2071 and 2084, then 10.1 billion in 2100.
The important pattern is hidden inside the numbers. Work out what each decade added:
Decade
World population (Fig. 6.4)
Added in the decade
Growth in the decade
1951 → 1961
2.5 → 3.0 billion
0.5 billion
20%
1971 → 1981
3.7 → 4.5 billion
0.8 billion
21.6%
1991 → 2001
5.4 → 6.2 billion
0.8 billion
14.8%
2011 → 2021
7.1 → 7.9 billion
0.8 billion
11.3%
2041 → 2051
9.2 → 9.7 billion
0.5 billion
5.4%
2071 → 2084
10.2 → 10.2 billion
0
0%
The world kept adding roughly the same 0.8 billion per decade for fifty years, yet the rate of growth fell from about 21% to about 11%. That is because the same addition is being made to a bigger and bigger base. Eventually even the addition shrinks, and the curve levels off.
India (Fig. 6.5) went from 361 million in 1951 to 1,460 million in 2025:
1460 ÷ 361 = 4.04 times — India’s population has just over quadrupled since 1951
The decadal figures are 361 (1951), 439, 548, 683, 846, 1020, 1210 (2011) and 1460 million (2025). The additions rose steadily — 78, 109, 135, 163, 174, 190 million — but the growth rate fell from about 24.8% in 1961–71 to about 14% a decade now. In 2023 India passed China to become the most populous country. Checking the chapter’s claim that Indians are around 17 per cent of the world:
144 crore ÷ 820 crore = 0.176 = about 17.6 per cent — the chapter’s “around 17 per cent” checks out
Why the curve has this shape is the heart of the chapter. Population growth is not the birth rate; it is the gap between births and deaths.
The three stages of demographic transition (Fig. 6.12). Population growth is not the birth rate — it is the gap between the blue and red curves. The gap opens in Stage 2 only because deaths fall before births do.
Why the gap opened, then closed: from the 1950s onwards, antibiotics, vaccines and oral rehydration solution arrived, water and sanitation improved, and child deaths from malaria and diarrhoea fell. Deaths fell first. Births, however, are decided by family customs and expectations, which change over a generation, not in a year — so births stayed high while deaths collapsed, and the gap between the two curves became enormous. That gap is the population explosion after 1950. Later, as girls’ education spread, women took formal jobs and cities became expensive, families chose to be smaller — so births fell too, the gap narrowed, and growth slowed. Nothing in this story requires people to have started dying more; the slowdown comes entirely from the birth side.
Growth is also uneven across countries. China, Japan and Italy already have shrinking populations, India’s is still growing for now, and several African nations such as Nigeria and Ethiopia continue to grow rapidly — because they are at different points along the same three-stage path.
Q4.
How do population trends shape societies and economies?
Answer
Because the age structure of a population decides what a society must build, who does the work, and who pays for it. The chapter follows this through in three directions.
1. A young population creates growth potential — if it is invested in. India has nearly 65 per cent of its people in the working-age group of 15–59 and a median age of 28 (Fig. 6.17). Young people work in factories, offices and farms or start businesses, so the volume of economic activity rises; they also earn and pay taxes, which the government uses to build schools, hospitals, roads and parks. That growth potential is the demographic dividend. The chapter is careful to call it a “window of opportunity”, and says developing countries must “harness the demographic dividend through investment in good education, skilling and healthcare”.
2. An ageing population reverses every one of those arrows. When people retire there are fewer workers to replace them, which can slow the economy; older adults need more healthcare; and governments struggle to pay pensions and provide services because there are fewer young taxpayers. China is the chapter’s worked example:
China
Then
Now / projected
Change
Fertility rate
7.5 (1963)
1 (2025)
fell to about one-seventh
Population
peaked at 1.43 billion (2022)
1.31 billion (2050)
a fall of 120 million, about 8%
Share aged over 65
14% (2023)
26% (2050)
nearly doubles, +12 percentage points
3. Population change reshapes families and places, not just economies. China’s One-Child Policy left “a whole generation of children [who] do not have siblings and kinship networks” — a social effect that outlasted the policy, which ended in 2015. Migration reshapes geography: Delhi, Mumbai and Bengaluru grew rapidly because people moved there for work and education, but concentrating a very large population in a limited area strains water, air and land, and puts pressure on transport and housing.
The idea underneath all three: people are simultaneously producers and dependants, and which one they are depends on their age. A country’s prosperity therefore depends less on how many people it has than on what fraction of them are of working age, and whether those people are educated, healthy and employed. That is why Japan, with far fewer people than India, faces a labour shortage — and answers it by raising the retirement age and using automation, robots and AI assistants to care for older adults.
One trend the chapter singles out for India: as more women take formal jobs they often face a double burden of job responsibilities and household duties. Without childcare facilities, joint-family support or flexible hours, many cannot stay in the workforce — so daycare centres and supportive family systems are part of what turns a demographic dividend into lasting progress.