Final answer:
Marcia used 5 lemons in the first 4 hours of her lemonade stand.
Step-by-step explanation:
To find how many lemons Marcia used in the first 4 hours, we need to determine the total number of cups of lemonade made in that time and then convert it to the number of lemons used. Based on the chart, Marcia sold 5 cups in the first hour, 4 cups in the second hour, 6 cups in the third hour, and 3 cups in the fourth hour. So, the total number of cups in the first 4 hours is 5 + 4 + 6 + 3 = 18 cups.
Since 10 cups of lemonade require 3 lemons, we can set up a proportion:
10 cups/3 lemons = 18 cups/x lemons
Cross-multiplying gives us 10x = 3 * 18, which simplifies to 10x = 54. Dividing both sides by 10 gives us x = 5.4.
So, Marcia used 5.4 lemons in the first 4 hours. However, since you can't have a fraction of a lemon, we can round it to the nearest whole number. Therefore, Marcia used 5 lemons in the first 4 hours.