3.1.7 Demographics — section quiz

Before you start: rates are just ratios

This whole quiz leans on one math skill — reading a rate like "12.5 per 1,000" and knowing what to do with it. If rates feel slippery, this clears that up before the vocabulary piles on.

Rabbit Nation: what the story's numbers really mean

The lesson opens with a story: Rabbit Nation starts with 1,000 rabbits. During the year, 1,000 more are born and 100 die. Do the arithmetic straight: 1,000 + 1,000 − 100 = 1,900 rabbits by year's end.

Rabbit Nation: what the story's numbers really mean (2)

That's a net gain of 900 rabbits over a starting population of 1,000 — a 90% natural increase for the year (900 ÷ 1,000).

The story's own labels — and why they're confusing

The lesson's own narration calls the birth count a "birthrate of 2.0," the death count a "death rate of 0.1," and 2.0 − 0.1 a "growth rate of 1.9." Those labels don't match the standard births per 1,000 population statistic the lesson uses correctly later (see the next card) — applied that way, this same story would be a birthrate of 1,000 per 1,000 and a death rate of 100 per 1,000.

The story's own labels — and why they're confusing (2)

What 1.9 actually is: the ending population as a multiple of the starting population — 1,900 ÷ 1,000 = 1.9×. That's an ending multiplier, not a rate. If a quiz question uses the story's own wording and asks for "the growth rate" of Rabbit Nation, the course's expected answer is 1.9 — just know that what you're really reporting is how many times bigger the population got, not a standard demographic rate.

Turning a rate into a real number

Here's the standard version, used correctly later in the same lesson: birthrate is genuinely stated per 1,000 people, and it's a ratio you can work forward or backward from a real headcount. The course's own worked example: a country with a birthrate of 12.5 and a population of 22 million had 275,000 births that year.

Turning a rate into a real number (2)

The math: 12.5 ÷ 1,000 = 0.0125. Multiply by the population: 22,000,000 × 0.0125 = 275,000.

Turning a rate into a real number (3)

Growth rate from births and deaths alone (birthrate minus death rate) is sometimes called the natural increase rate — it leaves out migration. A country's total population growth also depends on its migration rate, so "subtract death rate from birthrate" only tells you the natural piece, not the whole picture.

Population vs. population density

The lesson's own three-choice question asks which statement is true: (A) Utah has a larger population than Bangladesh, (B) Bangladesh is geographically larger than Utah, or (C) Bangladesh has more people in less space than Utah. The correct answer is C — Bangladesh's population (in the hundreds of millions) is vastly larger than Utah's (a few million), and Bangladesh packs that population into a much smaller area, making it one of the most densely populated countries on Earth. Utah, by contrast, is one of the more sparsely populated U.S. states.

Population vs. population density (2)

The lesson does make one genuine comparison point: Utah has the highest birthrate and fertility rate of any U.S. state, which the lesson calls "relatively close" to Bangladesh's. That comparison is about rates, not population size or density — a reminder that population density (people per unit of area) is a separate measurement from birthrate, fertility rate, or total population, and they don't automatically move together.

Comparing two real countries: Germany and Indonesia

This is the course's full worked comparison, and it's exactly the shape a quiz question is likely to copy. The numbers:

Comparing two real countries: Germany and Indonesia (2)

• Population density: Germany 230 people/km², Indonesia 122 people/km² — Germany is more crowded by this measure, even with far fewer total people.
• Birthrate: Germany 8.2 per 1,000, Indonesia 19.65 per 1,000 — Indonesia's is more than double.
• Death rate: Germany 10.71, Indonesia 6.25 (both per 1,000).
• Migration rate: Germany +2.18 (positive — more people arriving), Indonesia −1.27 (negative — more people leaving).
• Growth rate: Germany −0.033% (shrinking), Indonesia +1.213% (growing).

Comparing two real countries: Germany and Indonesia (3)

Put together: Germany's population is aging and shrinking, held roughly level only by people moving in. Indonesia's population is young and growing from births, even though more people are leaving than arriving.

Migration rate, and who counts as what

A migration rate is immigrants minus emigrants per 1,000 people. Every person who moves is simultaneously an emigrant (leaving one place) and an immigrant (arriving in another) — the same move, counted from two sides.

Push factors, pull factors, and the New York/Atlanta example

Push factors are reasons to leave a place — war, persecution, overcrowding, high unemployment. Pull factors are reasons to go toward a place — jobs, favorable climate, political stability.

Push factors, pull factors, and the New York/Atlanta example (2)

When push factors are extreme — war, persecution, government relocation — people are coerced into leaving. That's forced migration, also called displacement. Most migration, though, is voluntary migration: people choosing to leave because the push and pull are strong enough.

Push factors, pull factors, and the New York/Atlanta example (3)

The course's own numbers: New York City loses about 211,000 people a year to domestic migration (strong push: crowding, high cost of living, long commutes), while Atlanta gains roughly 31,000 a year (pull: more space, lower living costs, even though average wages are lower there).

Why cities keep growing

In 1950, about 70% of the world's population was rural and less than 30% was urban. The course describes the share of the world living in urban areas as having climbed since then, and expects it to keep climbing. The process of a society becoming more city-oriented is urbanization.

Why cities keep growing (2)

Two engines drive it, per the course: industrialization moves jobs into cities (factories need workers, workers need factories — a self-reinforcing cycle), and culture pulls people too (more to do, more people to meet).

Urbanism, metropolitan areas, and the tradeoffs of city life

The United States is the course's own example of strong urbanism — a culture centered on dense living, working, and recreation — even though the country still has wide-open rural land. Most Americans, per the course, now live inside one metropolitan area or another, where a city center spreads out through suburbs and satellite towns.

Urbanism, metropolitan areas, and the tradeoffs of city life (2)

City life has upsides the course names — cultural mixing, tolerance, opportunity — and downsides: crowding, cost pressure, and more friction between different groups of people living close together.

The world's population explosion

The last time world population actually decreased, per the course, was the 1300s, during the Black Death — a pandemic that killed an estimated 75 million people, including about a third of Europe. Growth sped up dramatically after the Industrial Revolution: it had taken centuries to double the population before then, but the 18th century managed it in about 100 years. In the 20th century, the course states, population doubled twice: from 1.5 billion (1900) to 3 billion (1960), then to 6 billion (2000). The course states world population passed 7 billion in 2011.

The world's population explosion (2)

This pattern — death rate falling first as a society industrializes, with birthrate staying high a while longer, producing a population boom in between — is demographic transition. Eventually birthrate falls too, usually because raising children gets more expensive, and the population levels off again at a much larger size.

Cartograms: resizing the world by a number, not land

A cartogram distorts the area of countries to represent something other than land size — population, GDP, energy use. Look at the world population and GDP cartogram below: countries don't just change color, their actual shapes balloon or shrink. China and India swell hugely on the population map because of their populations, not their land area.

Cartograms: resizing the world by a number, not land (2)

Compare that with an ordinary thematic map, like the population-growth-rate map further down this card: every country keeps its real size and shape, and only the color changes to show the data. That's the test — a cartogram resizes shapes; a thematic map just recolors them.

Final checklist

Tick these off as you go. Saved in this browser.

• I can do the Rabbit Nation arithmetic myself: 1,000 + 1,000 − 100 = 1,900, and find the 90% natural-increase rate from it.
• I know the course's own "growth rate of 1.9" is really an ending-population multiplier (1,900 ÷ 1,000), not a standard rate — and I can give the course's expected answer anyway if a question uses its wording.
• I can calculate a birth, death, or growth rate from a population and a given rate, like the course's 22-million/12.5-birthrate example.
• I know birthrate minus death rate gives natural increase only — total growth also needs the migration rate.
• I know Bangladesh has both a far larger population AND a far higher density than Utah — not just higher density.
• I can walk through the full Germany/Indonesia comparison: density, birthrate, death rate, migration rate, and growth rate.
• I can define push factor, pull factor, forced migration, and voluntary migration, and tell them apart in an example.
• I can explain industrialization and culture as the two drivers of urbanization, with the 1950 rural/urban split as a reference point.
• I can put the stages of demographic transition in order and say which rate drops first.
• I can tell a cartogram apart from a thematic map by whether the shapes themselves resize.
• I scored well on the practice quiz below, not just recognized the vocabulary.