Answer
30 muffins
Work Step by Step
We will call x the cups of flower and y the number of muffins made. We first solve for k. Thus, we plug in the points and solve for k:
$ y=kx \\\\ 12=(1)k \\\\ k=12$
We substitute k back in to get the equation: $y=12x$
We now plug in 2.5 cups to obtain: y=12(2.5)= 30 muffins.