Final answer:
The unit rate in terms of cups of orange juice to pineapple juice is 3:1.
Step-by-step explanation:
To find the unit rate in terms of cups of orange juice to pineapple juice, we need to compare the amount of each juice used in the punch. The punch uses 3/4 of orange juice for every 1/4 of pineapple juice. This means that for every 1 cup of pineapple juice, 3 cups of orange juice are used.
Therefore, the unit rate in terms of cups of orange juice to pineapple juice is 3:1.