Hiya there!
If the recipe provided says that we need two cups for three gallons of punch, then you need 2/3 of a cup for one gallon.
I know this because if you add 2/3+2/3+2/3 (or multiply 2/3×3), you get the whole integer 3.
If you found this especially helpful, I'd appreciate if you'd vote me Brainliest for your answer, if other people did not provide a helpful answer (but, I'm sure they did!). I want to be able to assist more users one-on-one! :)
