0.45 as a fraction.
As this fraction is rounded to the hundredths, simply put 45 as the numerator, and 100 as the denominator.
45/100
However, this is not the simplest (lowest) form, so we must simplify this.
Divide both the numerator (top number) and the denominator (bottom number) by 5.
45 ÷ 5 = 9
100 ÷ 5 = 20
So, we now have 9/20
That is the simplest it can be.
~Hope I helped!~