A punch recipe calls for cups of 1 2/3 orange juice, 3/4 cup of pineapple juice, and 1 1/2 cups of mango juice. How many total cups of fruit juice does the recipe make?

First turn the whole numbers into mixed fractions:

1 1/2

multiply the whole number by the denominator then add it to the numerator which will make 3/2

doing the same thing on 1 2/3, you get 5/3

finding the LCM of 5/3, 3/2 and 3/4, you get 12

multiplying 4/4 to 5/3, you get 20/12

multiplying 6/6 to 3/2, you get 18/12

multiplying 3/3 to 3/4, you get 9/12

now you can add them easily and you get 47/20

turning that into a whole fraction, you get 2 7/20