# How do you increase £80 by 20%?

Nov 24, 2016

I have shown 3 approaches

£96

#### Explanation:

The % sign is a unit of measurement and it is worth $\frac{1}{100}$

so 20% $\to 20 \times \frac{1}{100} = \frac{20}{100}$

so 20% of £80 is: " "20/100xx£80 = £16.00

As this is increase we have £80+£16 = £96

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$\textcolor{b l u e}{\text{Or you can also do it like this:}}$

$\frac{20}{100} \equiv \frac{20 \div 20}{100 \div 20} = \frac{1}{5}$

so 20% of £80 is: " "1/5xx£80 = £16.00 and the rest as above.

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$\textcolor{b l u e}{\text{Or you can also do it like this:}}$

£80(1+1/5) = £80+£16=£96