Final answer:
To serve 39 people, when a recipe calls for 4 boxes of rice for 13, set up the proportion 4/13 = x/39 and solve for x to find that you will need 12 boxes of rice.
Step-by-step explanation:
If a recipe calls for 4 boxes of rice to serve 13 people, you can calculate the number of boxes needed to serve 39 people by setting up a proportion. You can use the following steps to find the answer:
- First, determine the rate at which boxes serve people, which in this case is 4 boxes for 13 people.
- Set up a proportion to find out how many boxes are needed to serve 39 people. The proportion will be 4 boxes/13 people = x boxes/39 people.
- Cross-multiply to find the value of x. The equation looks like this: 4 × 39 = 13 × x.
- Solve for x by dividing both sides by 13, which results in x = (4 × 39)/13.
- Calculate the value of x, which gives you the number of boxes needed.
After solving the equation, the number of boxes needed to serve 39 people is 12 boxes of rice.