Select the correct answer.

Amy hikes 6 miles from a ranger station to a waterfall and back again. She hikes 1 mile/hour faster on the way back. Function [tex]$T$[/tex] represents Amy's total time spent hiking, and [tex]$x$[/tex] represents Amy's hiking speed in miles/hour.
[tex]
T(x) = \frac{6}{x} + \frac{6}{x+1}
[/tex]

Which phrase best describes the term [tex]$\frac{6}{x}$[/tex]?

A. It is the time it takes Amy to hike back to the ranger station.
B. It is the time it takes Amy to hike to the waterfall.
C. It is the distance that Amy hikes to the waterfall.
D. It is the speed at which Amy hikes to the waterfall.



Answer :

Let's analyze the problem in detail:

Amy hikes a total of 6 miles from a ranger station to a waterfall and then returns the same distance back to the ranger station, making a round trip of 12 miles total.

The function [tex]\( T(x) \)[/tex] is given as:
[tex]\[ T(x) = \frac{6}{x} + \frac{6}{x+1} \][/tex]
where [tex]\( x \)[/tex] represents Amy's hiking speed in miles per hour.

To understand the term [tex]\( \frac{6}{x} \)[/tex]:

1. Analyze the first term [tex]\( \frac{6}{x} \)[/tex]:
- The term [tex]\( \frac{6}{x} \)[/tex] represents the time it takes to cover the 6-mile distance at a speed of [tex]\( x \)[/tex] miles per hour.
- Time is calculated using the formula [tex]\( \text{Time} = \frac{\text{Distance}}{\text{Speed}} \)[/tex].
- Since [tex]\( x \)[/tex] is Amy’s hiking speed on the way to the waterfall, [tex]\( \frac{6}{x} \)[/tex] measures the time it takes her to hike to the waterfall.

2. Analyze the second term [tex]\( \frac{6}{x+1} \)[/tex]:
- The term [tex]\( \frac{6}{x+1} \)[/tex] represents the time it takes Amy to return the 6 miles to the ranger station.
- On the return trip, Amy hikes 1 mile per hour faster, thus her speed is [tex]\( x + 1 \)[/tex] miles per hour.
- The time taken for the return trip is given by [tex]\( \frac{6}{x+1} \)[/tex].

Given this understanding, we can now evaluate the options:

- Option A: It is the time it takes Amy to hike back to the ranger station.
- This is incorrect because [tex]\( \frac{6}{x} \)[/tex] is the time taken to hike to the waterfall, not back to the ranger station.

- Option B: It is the time it takes Amy to hike to the waterfall.
- This is correct because it aligns with our understanding that [tex]\( \frac{6}{x} \)[/tex] measures the time to hike the 6 miles to the waterfall at speed [tex]\( x \)[/tex].

- Option C: It is the distance that Amy hikes to the waterfall.
- This is incorrect because [tex]\( \frac{6}{x} \)[/tex] measures time, not distance.

- Option D: It is the speed at which Amy hikes to the waterfall.
- This is incorrect because [tex]\( \frac{6}{x} \)[/tex] measures time, not speed.

Therefore, the correct phrase that best describes the term [tex]\( \frac{6}{x} \)[/tex] is:

B. It is the time it takes Amy to hike to the waterfall.