advice required on ratio calculation formula

Hi All,

Excel Newbie here...

i work in catering and need to work out a simple calculation in excel regarding amount of catering to load.

The example i have is regarding a tray of desserts, the loading ratio is 1 tray per 20 people..

if i have 61 people then i need to load 4 trays in total, but i cant seem to work this out on excel, i tried division but this only gives me 3 trays ofcourse, (its probably super basic!)

I know i can do a look up but i would prefer not to as the menu/ratios are continuously changing.

appreciate any guidance on this