One may note, you never quite asked anything per se, ahemm, if you meant simplification.
For a single 25 pound case you can make 133 servings, As a single pound of tomatoes equals 16 ounces; and 16x25 is 400, and when you divide that be 3 it turns into 133.3333333- and goes on, but you round that down to 133 for your answer.
7 is the lowest common multiple i think