The chart below shows how many cups of lemonade Marcia sold each hour she had her lemonade stand set up. To make 10 cups of lemonade, Marcia has to squeeze 3 lemons. How many lemons did Marcia use in the first 4 hours?

Step-by-step explanation:

Given

See attachment for chart

Required:

Lemons used in first 4 hours

First, we calculate the number of lemon sold in the first 4 hours.

Represent the number of cups of lemonades needed with x

So, we have:

and

Cross Multiply:

Make x the subject

cups