So in order to find the answer, let us analyze the given graph first. As we can see, for every 2 cups of flour you get 1 batch of cookies. So this gives us the ratio is 2 to 1. When we say constant proportionality, this is the <span>constant value of the ratio of two proportional quantities. Since for every 2 cups added, the batch of cookies is increased by 1, which gives us the constant proportionality of 2. Hope this answer helps.</span>