Final answer:
The cyclist will travel a distance of 4 miles.
Step-by-step explanation:
To find the distance the cyclist will travel, we need to calculate the distance covered in the given time. The cyclist travels at a constant speed of 12 mph for 20 minutes, which is 1/3 of an hour. To calculate the distance, we multiply the speed by the time:
Distance = Speed x Time
Distance = 12 mph x 1/3 hour = 4 miles
Therefore, the cyclist will travel a distance of 4 miles.