Express the following as a fraction in simplest form :

0.45

We have:

0.45

There are 2 decimal places, so we remove the decimal point and divide by 100.

$\phantom{=} 0.45 = \dfrac{45}{100} \\[1em] = \dfrac{9}{20} \quad \text{[Dividing both by 5]}$

∴ The answer is $\dfrac{9}{20}$