Rosa has 4 1/2 pounds of pizza dough. she uses 3/4 of a pound for one pizza. how many pizzas could be made from rosa's dough?

Amount of pizza dough that Rosa has = 4 1/2 pounds
                                                               = 9/2 pounds
Amount of dough required by Rosa to make 1 pizza = 3/4 pounds
Then
The number of pizza that can be made with 9/2 pounds of dough = 1/(3/4) * (9/2)
                                                                                                         = (4/3) * (9/2)
                                                                                                         = 2 * 3
                                                                                                         = 6
So Rosa can make 6 pizzas with the amount of dough she has. I hope the procedure is clear enough for you to understand. Glad to have helped you.