Answer: [tex]7\dfrac12[/tex] cups of flour is required for 3 sticks of butter.
Step-by-step explanation:
We assume that quantity of flour is proportional to butter.
Given : The recipe calls of [tex]1\dfrac14[/tex] cups of flour and [tex]\dfrac12[/tex] stick of butter.
Let [tex]x_1=1\dfrac14=\dfrac{5}{4}[/tex] [tex]y_1=\dfrac{1}{2}[/tex]
For [tex]y_2=3[/tex] , we will find [tex]x_2[/tex] by using formula of direct proportion: [tex]\dfrac{x_1}{y_1}=\dfrac{x_2}{y_2}[/tex]
[tex]\dfrac{\dfrac{5}{4}}{\dfrac12}=\dfrac{x_3}{3}\\\\\Rightarrow\ \dfrac{5}{2}=\dfrac{x_3}{3}\\\\\Rightarrow\ x_3=\dfrac{5}{2}\times3= \dfrac{15}2=7\dfrac12[/tex]
Hence, [tex]7\dfrac12[/tex] cups of flour is required for 3 sticks of butter.
