Stu hiked a trail at an average rate of 3 miles per hour. he ran back on the same trail at an average rate of 5 miles per hour. he traveled for a total of 3 hours. which equation can be used to find the time it took stu to hike the trail?

D=3h and d=5r, since d=d

3h=5r  and we are told that h+r=3 so r=3-h making the equation become:

3h=5(3-h)

3h=15-5h  add 5h to both sides

8h=15  divide both sides by 8

h=1.875 hrs  (1:52:30)

So Stu hiked for 1.875 hours.  (1 hour 52 minutes and 30 seconds)

check...

3(1.875)=5(3-1.875)

5.625=5(1.125)

5.625=5.625  (and it also shows the that trail was 5.625 miles long)