4.5/45 simplified?

Start by multiplying the top and bottom by 10.

$$\frac{4.5}{45}$$

$$\frac{4.5\times10}{45\times10}$$

$$\frac{45}{450}$$

Divide the top and bottom by 45

$$\frac{1}{10}$$

4.5 is the same as 45/10 so if we split 4.5/45 into two fractions:

45/10 * 1 / 45

45/450

Divide both the top and bottom by 45:

1 / 10.