In the question it is given that the length of the blue lake trail is 11 3/8 miles. In the question it is also given that Gemma has hiked for a total time of 3 hours and each hour she has hiked 2 1/2 miles.
Now coming to solving the problem we get:
Total length of blue lake trail = 11 3/8 miles
= 91/8 miles
Distance hiked by Gemma in 1 hour = 2 1/2 miles
= 5/2 miles
Then the total distance hiked by Gemma in 3 hours = (5/2) * 3
= 15/2 miles
The distance left to cover the full trail = (91/8) - (15/2) miles
= (91 - 60)/8 miles
= 31/8 miles
= 3 7/8 miles.
So Gemma is 31/8 miles or 3 7/8 miles from the end of the trail.
In order to rationalize the denominator of each expression, we need to multiply the expression by the same radical in the denominator, this way we can remove the radical from the denominator.
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D is the answer.. hope u didn’t stress yourself out with that question