To make 48 cups of punch, use 28 cups apple juice and 20 cups cranberry juice.
A proportion is an equation in which there are two ratios are set equal to each other. For example, if there is one guy and four girls, the ratio may be written as 1: 4, which means for every 1 guy there are 4 girls.
In this problem, we can write the ratio of apple juice, cranberry juice, and fruit punch as:
apple juice: cranberry juice: fruit punch = 7: 5 : 12
Now you want to make 48 cups of fruit punch. We can ask, how do we get 48 from 12? It should be multiplied by 4. Hence, all numbers in the above proportion should be multiplied by 4.
Thus, apple juice: cranberry juice: fruit punch = 7: 5: 12
= (7 x 4) : (5 x 4) : (12 x 4)
= 28: 20: 48
Hence, you need 28 cups of apple juice and 20 cups of cranberry juice.
Question:
A recipe for fruit punch calls for 7 cups of apple juice for every 5 cups of cranberry juice, and you want to make 48 cups of fruit punch. How many cups of each juice do you need to make a total of 48 cups of fruit punch?