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Succeed with maths: part 1

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# 1 Using percentages

Take a look at the two t-shirts in Figure 1 which are on sale. Which shop is offering the better deal? You’ll find out how to work this out and questions like it this week.

Figure 1 Finding the best deal

First, start by trying a refresher activity before moving onto some new ideas.

You will definitely find a calculator useful for Activity 1, which involves population figures.

## Activity 1 Writing one number as a percentage of another

Timing: Allow approximately 10 minutes
• a.In 2020, the population of the European Union was about 447 700 000, and the total population of the Republic of Ireland was about 4 940 000. What was the population of the Republic of Ireland as a percentage of the total population of the European Union?

Hint: to find the percentage, you write the numbers as a fraction and multiply by 100.

First write the two numbers as a fraction:

Then multiply by 100, to give:

The answer is rounded to 1 decimal place. By necessity, population figures are estimates – so showing the answer any more accurately would not make sense in this case.

Rounded to 1 decimal place, the population of the Republic of Ireland was 1.1 per cent of the total population of the European Union in 2020.

• b.Now looking at one of the larger member states – Germany, which had a population of around 83 800 000 in 2020. Find the population of Germany as a percentage of the total population of the European Union, rounding your answer to 1 decimal place again.