A recipe for one batch of cookies uses 5 cups of flour and 2 teaspoons of vanilla.

Complete the double number line diagram to show the amount of flour and vanilla needed for 1, 2, 3, 4, and 5 batches of cookies.

If you use 20 cups of flour, how many teaspoons of vanilla should you use?

If you use 6 teaspoons of vanilla, how many cups of flour should you use?

Explain how you would determine how much flour and vanilla would be needed for 9 batches of this cookie recipe.