Description: Working example comparing constants of proportionality. Betty's Bakery calculates the total price D in dollars for C cupcakes using the equation D is equal to two times C. Alright, before I even look at the choices, let me just interpret this. This says D equals 2C tells us that however many cupcakes someone buys, we multiply that times two to get the amount of dollars, the price that they need to pay. So let's see, choice A says the bakery charges two dollars for each cupcake.*Teacher Advisor is 100% free.