4/3 is the ratio between fruit punch and orange juice. For every 3 cups of orange juice she makes, she can make 4 fruit punches. An example: If you replace x (orange juice) with 2, that'd mean there'd be 6 cups of orange juice because you'd multiply 3 and 2. Same goes to 4. 4 multiplied by 2 is 8, which means if she makes 6 cups of orange juice, she can make 8 cups of fruit punch.
