Mary is baking a cake. The recipe calls for 9 cups of sugar and 45 cups of flour. She already put in 2 cups of flour. How many more cups of flour than cups of sugar does she need to add now?
First, we need to figure out how many cups of sugar she has left to add. We know she's already put in 2 cups of flour, and the recipe calls for 9 cups of sugar. So she has 9 - 2 = 7 cups of sugar left to add. 

Next, we need to figure out how many cups of flour she has left to add. We know she's already put in 2 cups of flour, and the recipe calls for 45 cups of flour. So she has 45 - 2 = 43 cups of flour left to add. 

Finally, we need to figure out how many more cups of flour than cups of sugar she needs to add. We know she needs to add 7 cups of sugar and 43 cups of flour. So she needs to add 43 - 7 = 36 more cups of flour than cups of sugar.