Ni’Kieylah uses 3 cups of sugar for every 2 teaspoons of baking soda to make a batch of cookies.  Which proportion could be solved to find x, the number of teaspoons of baking soda needed for 9 cups of sugar?

3/2 = 9/x

Cross multiply:

3x = 18

Divide by 3 on both sides:

x = 6

Therefore, 6 teaspoons of baking soda are needed for 9 cups of sugar.