Billy made 2 1/4 of 3 gallons less than he needed. Draw a G stands for gallon. Now draw 4 Q's inside the G. The q's stand for quarts. There are 4 quarts per gallon and he needs 3 gallons. If he only makes 3 out of 4 quarts, (3/4) he has 2 and 3/4's less than what he needs.
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