Everyday maths 1 (Wales)
Everyday maths 1 (Wales)

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Everyday maths 1 (Wales)

5.2 Finding percentages using a calculator

There are different ways to work out percentages on a calculator. You can work out any percentage on a calculator by dividing by 100 first (to find 1%) and then multiplying the amount by the percentage you need.

If you were asked to work out 20% of 80, you could do the following:

80 ÷ 100 = 0.8

0.8 × 20 = 16

However, most calculators (including those on a mobile phone) will often have a percentage button. The percentage button looks like this:

Described image
Figure 30 The percentage button on a calculator

To successfully use it when calculating percentages you would enter the sum into your calculator as follows.

If you were asked to find 20% of 80, on your calculator you would input:

80 × 20%

This would give you the following answer:

80 × 20% = 16

If you were asked to find 20% of 80, on your calculator you would input:

20% × 80

This would give you the following answer:

20% × 80 = 16

Different calculators may work in different ways so you need to familiarise yourself with how to use the % button on your calculator.


In this section you have learned how to solve problems using percentages, and how to calculate percentage increases and decreases.


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