Question

A cookie recipe calls for 5/7 cup of butter to make 4 dozen cookies. Mackenzie need to make 18 dozen cookies for a bake sale. How many cups of butter are required?

Answer 1

Given data:

5/7 cup of butter to make 4 dozen cookies

? cup of butter to make 18 dozen cookies

Use a rule of three:

`\begin{gathered} ?=(18*(5)/(7))/(4) \\ \\ ?=((90)/(7))/(4) \\ \\ ?=(90)/(7*4) \\ \\ ?=(90)/(28) \\ \\ ?=(45)/(14)=(42)/(14)+(3)/(14)=3(3)/(14) \end{gathered}`Then, there are required 45/14 (or 3 3/14) cups of butter to make 18 dozen of cookies