To determine the probability that the first student in line for lunch will be served their preferred beverage, we need to focus on the drinks that are actually served by the school: milk, chocolate milk, and water.
Let's break down the problem step-by-step:
1. Identify the relevant percentages:
- Milk/Chocolate Milk: 26%
- Water: 13%
2. Add the percentages of the drinks that are served:
- Milk/Chocolate Milk + Water = 26% + 13% = 39%
3. Convert this percentage into a probability:
- Since probability is typically expressed as a number between 0 and 1, we convert 39% to its decimal form:
- 39% = 0.39
Therefore, the probability that the first student in line will be served their preferred beverage (either milk, chocolate milk, or water) is 0.39.
So, the correct answer from the given options is:
0.39
