Respuesta :

Answer

Explanation:

Britanny wants to make cookies

The recipe for making one cookie is 2 1/4 cups flour

The total number of cups she has is 9 cups of flour

Step 1: convert the mixed fractions into an improper fraction

2 1/4 = (4 x 2) + 1 / 4

2 1/4 = 8 + 1/ 4

2 1/4 = 9/4 cups

1 batch of cookie = 9/4 cups

b batches of cookies = 9 cups

Cross multiply

1 x 9 = b x 9/4

9/4 b = 9

Cross multiply

9b = 9 x 4

9b = 36

Divide both sides by 9

9b/9 = 36/9

b = 4

Therefore, the answer is 2 1/4b = 9 and b = 4