Final answer:
Luis will take 36 minutes to run three miles, as the time needed is directly proportional to the number of miles, and this is calculated by multiplying the time for one mile (12 minutes) by three.
Step-by-step explanation:
If Luis takes 12 minutes to run one mile, then to find out how much time it will take him to run three miles, we simply need to multiply the number of miles by the time it takes for one mile. This is an example of a direct variation, where the time taken is directly proportional to the distance.
Here's the calculation:
- Time to run 1 mile: 12 minutes
- Time to run 3 miles: 12 minutes/mile × 3 miles = 36 minutes
Therefore, it will take Luis 36 minutes to run three miles.