Question

evas lemonade recipe calls for 2 cups of sugar and 9 lemons. in planning for the lemonade stand, eva plans to use 27 lemons. how many cups of sugar should she use?
10 yellow marbles / 45 green marbles =? / 9 green marbles

Explanation:

Step1: Set up proportion

Let $x$ be the number of cups of sugar. The proportion is $\frac{2}{9}=\frac{x}{27}$.

Step2: Cross - multiply

$9x = 2\times27$.

Step3: Calculate right - hand side

$2\times27 = 54$, so $9x=54$.

Step4: Solve for $x$

$x=\frac{54}{9}=6$.

Answer:

6