Ratios — Definition & Examples

I made this cake for my friend Liz's birthday. I am planning on adding some Kit-Kat bits on some of the slices since Liz loves Kit-Kats. However, some of our friends don't really like Kit-Kats (crazy, I know!) So I'm only putting Kit-Kats on $\frac{1}{4}$ of the cake. How many slices will have Kit-Kat bits on it?