Question

You need

1 1/4 cups of sugar to make 20 cookies

how many cups of sugar
to make 14 cookies

Answer 1

0.875 cups of sugar because
1.25=20
x=14
1.25*14/20

Answer 2

`\bf \begin{array}{ccllll} \textit{sugar cups}&cookies\\ \textendash\textendash\textendash\textendash\textendash\textendash&\textendash\textendash\textendash\textendash\textendash\textendash\\ 1 (1)/(4)&20\\ x&14 \end{array}\implies \cfrac{1(1)/(4)}{x}=\cfrac{20}{14}\implies \cfrac{(5)/(4)}{(x)/(1)}=\cfrac{20}{14} \\\\\\ \cfrac{5}{4}\cdot \cfrac{1}{x}=\cfrac{20}{14}\implies \cfrac{5}{4x}=\cfrac{20}{14}`

solve for "x"