How cities grow: urban, suburban and rural patterns
Grade 9 Social Studies Worksheet - Challenge Me
Circle the best answer.
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The largest urban areas, 2018
Urban area People (millions) Tokyo 37 Delhi 29 Shanghai 26 Mexico City about 22 São Paulo about 22 Cairo close to 20 Mumbai close to 20 Beijing close to 20 Dhaka close to 20 Note: UN World Urbanization Prospects (2018 Revision). In 2018, 33 megacities, each with more than 10 million people, were home to one in eight of the world's urban people; the UN projects 43 by 2030. Close to half of urban people live in places of fewer than 500,000 people. The UN projects that Delhi will become the largest urban area around 2028. Projected urban growth from 2018 to 2050: India 416 million, China 255 million and Nigeria 189 million, together 35% of the world's urban growth. Megacity counts differ by source and method: 32 (EU Global Human Settlement Layer, 2024), 33 (UN DESA, 2025) and 39 (OECD, 2020). A city's site is the land it sits on; its situation is where it lies compared with other places. Pittsburgh's site is where the Allegheny and Monongahela rivers join to form the Ohio. The Ohio River flows southwest from Pittsburgh to the Mississippi River.
Close to half of urban people live in places under 500,000, and 33 megacities hold one in eight. What share lives in places between 500,000 and 10 million, Ari?
- About three-eighths, because one-half and one-eighth leave three-eighths for the places in between
- About one-quarter, because the middle class is the share left once megacities are removed
- About one-half, because the places in between match the small places in size
- About five-eighths, because one-half and one-eighth added together make five-eighths
Bo says megacities are where urban life mostly happens, since the biggest areas are the ones on the list. What do the cards show?
- Megacities hold one in eight, so the other seven in eight live in places under 500,000
- Megacities hold one in eight urban people, while close to half live in places under 500,000
- They are the main setting, since the largest areas are the ones named in the chart
- Close to half live in small places, so the other half live in megacities
Sources count 32, 33 and 39 megacities. Jun wants to explain why. Which explanation fits the cards?
- The counts are the same once the same 10 million threshold is applied to the same list
- The sources count by different methods, so their megacity counts differ
- The counts differ because the years differ, and 39 is the newest count of the three
- One of them is right and the UN's figure is the official one, so the others are simply errors of method
The UN counted 33 megacities in 2018 and projects 43 by 2030. Kira says that is a rise of about 30 percent in 12 years. Check it.
- Wrong: it is about 23%, since 10 is 23% of the new count of 43
- Wrong: it is about 10%, since 10 more megacities is a rise of 10 percent
- Right: 10 more on a base of 33 is about 30%, close to one new megacity a year
- Right, and the count rises by exactly one a year, so growth is steady
The cards say a megacity has more than 10 million people. Luz wonders whether this threshold makes the counts sharp. What is the sound point?
- The threshold shows that megacities differ in kind from smaller cities, not just in size
- The threshold makes counts exact, since a place either has more than 10 million or it does not, with no gray area
- A threshold sorts places by one number, so a place just under it is left out though nearly as large
- A place under 10 million is not a city, since the UN gives the name city to megacities alone
India, China and Nigeria add 416, 255 and 189 million urban people, which is 35% of the world's urban growth. How much do the other countries add, Milo?
- About 0.9 billion, since the other countries add about the same as the three do together
- About 0.5 billion, since the other countries add the remaining 35% of the growth in urban people
- About 0.3 billion, since 35% of 860 million is the share that the other countries add
- About 1.6 billion, since the three add 860 million, 35% of a world gain near 2.5 billion
Delhi (29 million) is projected to pass Tokyo (37 million) around 2028. What must be true of the gains until then, Noah?
- Delhi must grow by 8 percent more than Tokyo, since the gap between the two is 8 million people today
- Delhi must reach 37 million, the size Tokyo has today, before it can be the largest
- Delhi must gain more than Tokyo gains plus 8 million, so Delhi grows faster or Tokyo stalls
- Delhi must gain 8 million people, which is the gap between it and Tokyo today
India adds 416 million and China 255 million urban people from 2018 to 2050. Pia says India will have more urban people than China in 2050. What do the cards allow?
- That India will, because its gain of 416 million is larger than China's gain of 255 million
- That China will, because a larger country adds fewer people to its cities
- Nothing about 2050 totals: the cards give gains, not each country's urban people in 2018
- That they will have equal totals, because both gains are measured from 2018
Pittsburgh's site is where two rivers join. Which statement is about its situation rather than its site, Ren?
- It lies on the Ohio River, which flows southwest to the Mississippi River
- It rests on the ground at the meeting of two rivers
- It stands on the land where the Allegheny and Monongahela rivers join
- It sits at the point of land formed by two rivers meeting to form the Ohio
Pittsburgh sits where two rivers join. Zee says every large city sits where rivers join. Does Pittsburgh show that?
- Yes: the Ohio's flow to the Mississippi shows that large cities need river routes
- No: one city is an example of the idea, and it cannot show what holds for every large city
- No: Pittsburgh's site cannot be a river meeting, because a site is a point, not a place
- Yes: a river meeting is the site of Pittsburgh, so it is the site of every large city