The ratio of oranges in a fruit salad to people it will serve is 9/40, or 9:40. If Lisa wants to serve 800 people, how many oranges will Lisa use?

The correct answer is 180 oranges

Explanation:

In mathematics, a ratio expresses two or more numbers that are related. In the case fo the ration 9: 40 this expresses 9 oranges are used to serve fruit salad for 40 people. Now, if you need to determine what is the number of oranges not for 40 people but for 800 people you can use cross multiplication. This process is explained below:

  - 1. Multiply  9 x 800 and 40 x x (cross multiplication)

- 2. Solve the equation by diving 7200 into 40

- 3. 180 represents the number of oranges to serve 800 people, which   can be expressed as 180: 800