I’m late, sorry! But here is what I got : 1•15= 15 bags of popcorn. 3 3/4 • 15= 56 1/4 cups of pretzels . 2 1/4 • 15= 33 3/4 cups of m&m’s . Im not sure about the constant of proportionality but the equation to help solve it would be y=kx I’m pretty sure and I think the constant is 15 but it probably isn’t.