Answer:
18.75 gallons of ice
Explanation:
I divided the 2.5 gallons of ice by the number of buckets (4) it filled to determine how many gallons of ice are in each bucket.
2.5 / 4 = 0.625
I then multiplied the amount of ice it takes to fill a bucket (0.625) by 30 buckets to get 18.75 gallons of ice.