A scout troop plans to hike a 21-mile trail in the

Appalachian Mountains. They expect to hike the trail at a

rate of 3.5 miles per day. Which equation models the

relationships between the hiking time t they have

remaining on the trail and the number of days d they

have already hiked?

A. t = 21 (3.5d)

B. t = 21 - 3.5d

C. t = (21 - 3.5) d

D. t = 21 + 3.5d

Equation B

Step-by-step explanation:

By going through the equations and comparing them to the question, we can determine the correct equation.

Equation A is the multiplication of the distance they have already hiked by 21.

Equation B is the subtraction of the distance already hiked from the total length of the trail.

Equation C is the same as Equation A, but with a factor of 17.5 instead of 21.

Equation D is the addition of the distance already hiked from the total length of the trail.

Therefore, Equation B is the correct answer.