In a gallon, there are 4 quarts. That means 8 pints...
So there is 8 pints in a gallon. The question is asking for 3 gallons equals how much pints.
In one gallon, there are 4 quarts. In 4 quarts there are 8 pints. In 8 pints there are 16 cups. That means 1 gallon is 16 cups. The question is asking for 4 gallons however.
Multiply them to get your answer