Final answer:
After hiking for 3 hours at a speed of 2 1/2 miles per hour, Gemma has covered 7 1/2 miles of the Blue Lake trail, which is 11 3/8 miles long. Therefore, she is 3 7/8 miles from the end of the trail.
Step-by-step explanation:
The question asks how far Gemma is from the end of the trail after hiking for 3 hours at a speed of 2 1/2 miles each hour on the Blue Lake trail, which is 11 3/8 miles long.
To find out how far Gemma has hiked, we multiply the number of hours hiked by the speed per hour:
2 1/2 miles/hour × 3 hours = 7 1/2 miles
Next, to find out how far she is from the end of the trail, we subtract the distance she has hiked from the total length of the trail:
11 3/8 miles - 7 1/2 miles = 3 7/8 miles
So, Gemma is 3 7/8 miles from the end of the Blue Lake trail.