Mary is baking a cake. The recipe calls for 9 cups of sugar and 50 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: 

9 cups of sugar - 2 cups of flour = 7 cups of sugar

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 50 cups of flour, so: 

50 cups of flour - 2 cups of flour = 48 cups of flour

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 48 cups of flour, so: 

48 cups of flour - 7 cups of sugar = 41 cups of flour