Question

Mr. McDonald gave his math class the following problem. 18 pizzas need to be split among 12 families. How any pizzas does each family get? Different people in the class gave different answers. Which one is correct?
18\12 9\6 1\2 3\2 9\4 1 1\2
1 3\6 1 1\3
They are all fractions

Answer 1

The answer is 1 and 1/2

Answer 2

None of those choices is correct, because a bare naked fraction without units is not a satisfactory answer.  Keeping the units makes this question easy to answer, and the answer needs units.

The question is asking for a unit rate.  That always means DIVIDE.

                    (18 pizzas) / (12 families)

                 = ( 18/12 )      (pizza/family)  =  1.5 pizza/family .