Jaquan mixed 1 3/4 teaspoons of baking powder with 1 1/2 cups of flour to make a cake. Jasmine asked him to make some cake for her birthday party. To make a cake the birthday cake, Jaquan used exactly 9 cups of flour. How many teaspoons of baking powder should Jaquan use to make a birthday cake?

10¹/₂ of flour

Step-by-step explanation:

Jaquan mixed 1 ³/₄ teaspoons of baking powder with 1 ¹/₂ cups of flour to make a cake

which means

1 ³/₄ + 1 ¹/₂ = 2³⁺²/₄ = 2⁵/₄

⁵/₄ = 1¹/₄

adding ⁵/₄ to 2 = 1¹/₄ + 2 = 3¹/₄ to make cake

but to find the teaspoons of baking powder that Jaquan will use to make a birthday cake in the same ratio if Jaquan used exactly 9 cups of flour

we need to express it in ratio and

1 ³/₄ is baking powder

1 ¹/₂ is flour

x is the other baking powder we are looking for

9 is for flour

1 ³/₄ : 1 ¹/₂ = x:9

converting to whole improper fraction

1 ³/₄ = 4x1+3/4 = 4+3/4 = 7/4

1 ¹/₂ = 2x1+1/2 = 2+1/2 = 3/2

7/4:3/2 = x:9

7/4/3/2 = 7/4 x 2/3 = 7x1/2x3 = 7/6

7/6 = x/9

cross multiply

7x9 = 6x

63 = 6x

x = 63/6 = 21/2 = 10¹/₂ of flour