The World as a Village
Introduction
Today we will be looking at absolutely everyone! Take a look at the hyperlink about the world's population.
What is good rough estimate of the world's population?
How do you round it to the nearest billion?
How do you round it to the nearest million?
How do you round it to the nearest thousand in words?
How do you round it to 1 significant figures?
How do you round it to 2 significant figures?
How do you round it to 3 significant figures?
Look at this video if you are unsure how to round to significant figures.
If the world population is 8 billion rounded to the nearest billion, what is the error interval for the population?
If the world population is 7.8 billion rounded to the nearest 2 significant figures, what is the error interval for the population?
If the world population is 7.75 billion rounded to the nearest 2 decimal places, what is the error interval for the population?
Look at this video if you are unsure what error intervals a.k.a. upper and lower bounds are.
How do you write the population of the following countries in standard form?
China
India
US
UK
Look at this video and this video if you are unsure what standard form a.k.a. scientific notation is.
What is the total population of China and India?
What is the total population of US and UK?
How many more people are there in China than India?
How many more people are there in the US than the UK?
Look at this video if you are unsure how to add/subtract standard forms.
On average, a person drinks 1.82 x 102 gallons of water a year. How much water (in standard form) is drunk by people in each of the four countries above?
The GDP (Gross Domestic Product) of the four countries in standard form are as follows:
China - 1.77 x 1013 USD
India - 3.18 x 1012 USD
US - 2.33 x 1013 USD
UK - 3.31 x 1012 USD
Work out the GDP per capita of each country
Look at this video if you are unsure how to multiply/divide standard forms.
Further questions on percentages
Approximately how many females are there in the world?
If roughly 19% of the world's population live in China, how many people is that?
63 million people live in the UK. What percentage of the world's population is that?
If roughly one quarter of the population is under 15, how many children is that?
How many people live in the northern hemisphere if the north, south population ratio is 9:1 ?
What is the approximate increase in the population each minute?
When will the population reach 8 billion?
If everyone in the world lay end to end in a line, how long would that line be?
What is the total weight of all the people in the world?
If you counted everyone in the world how long would that take?
100 People
Take a look at this video. If the world were 100 people, who would we be? The video proportionally reduces the world population of 7.5 billion to 100 people.
What interesting facts did you notice?
Click here for some statistics for 2016. Is there anything else interesting you notice?
If 16 out of 100 people are Africans, how many Africans are there in a world of 7.5 billion?
If 14 out of 100 people would be not be able to read and write, how many would that be in a world of 7.5 billion?
Take a look at worldometers.info. Is there anything interesting you notice?
If roughly 862 million people out of 7.5 billion in the world are undernourished, how many would be in a village out of 100 people?
If roughly 13.9 million people out of 7.5 billion in the world live are Jews, how many would there be in a village out of 100 people?
Now research things that you are interested in about the world on worldometers.info and write different statements beginning with "If the world were 100 people, ..."
Make sure you show your calculations.
Note: the world population is no longer 7.5 billion!
Alternatively, research things that you are interested in about Hong Kong using this, the 2022 census or search things up using the HK Government Fact Sheets. Write different statements beginning with "If Hong Kong were 100 people, ..."
Alternatively, find out about your class!
Ask and answer each other questions (here are some questions asked by a previous Year 8 group, you may wish to make a copy).
Write different statements beginning with "If my year 8 maths class were 100 people, ..."
Make sure you show your calculations.
How could you present your findings graphically?
Further questions on percentages
Take a look at the 100 people statistics in 1990 and compare it to 2006?
How would you describe the changes?
What is the percentage change of muslim population?
What is the percentage change of people with have no clean, safe water to drink?
Calculate other interesting changes.
Take a look at worldometers on world population:
The world population in 2016 was 7,464,022,049 and the growth rate in 2016 was 1.14%, what was the population in 2017?
The world population in 2016 was 7,464,022,049 and the growth rate in 2015 was 1.19%, what was the population in 2015?
The world population in 2020 was 7,794,798,739 and the average growth rate is 1.10% per year, what will the population in 2025?
Further Practice
Some of the essential skills introduced in this lesson are "proportions", "percentages" and "percentage change". On top of that, we reviewed some previously learnt skills such as fractions, ratios, rounding to significant figures, upper and lower bounds, standard form etc. The relevant skills can be found on DrFrostMaths, CorbettMaths, MyiMaths and Eedi. Watch any video and/or go through any online lesson as you see fit.
Transum
Standard form:
Standard Form: Test your understanding of standard form (scientific notation) with this self-marking quiz.
Percentages:
Quick Percentages - practise calculating simple percentages in your head with this animated visual aid.
Visualise Percentages - if you can picture in your mind what a percentage looks like you may be better able to preform mental calculations
Estimating Percentages- estimate the percentages represented by the diagrams.
Express as a Percentage- this self-marking quiz requires you to work out what one quantity is as a percentage of a second quantity.
Fraction Percentage -match the fraction with the equivalent percentage. A drag and drop self marking exercise.
Fraction Percentage Pairs - the traditional pairs or Pelmanism game adapted to test knowledge of simple fractions and their equivalent percentages.
Fractions, Decimals, Percentages - an exercise on converting fractions to decimals, decimals to percentages and percentages to fractions.
Particular Pipes- construct the pipes using a set number of pieces with lengths given as fractions, decimals or percentages.
Percentage Change- test your understanding of using percentages with this self marking quiz about percentage change.
Percentage Switch - practise percentage increase and decrease calculations by completing this table.
Percentages Quiz - a multi-level quiz on finding percentages. The lower level questions can be done mentally while the highest level questions require a calculator.
Interest - practise using the formulas for simple interest and compound interest. - This is technically not part of what you need to know now, but have a go at it if you wish.