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A bus traveled on a level road for 3 hours at an average speed 20 miles per hour faster than it traveled on a winding road. The time spent on the winding road was 3 hours. Find the average speed on the level triad if the entire trip was 252 miles

User Saqib
by
4.3k points

2 Answers

1 vote

Answer: 52 mph

Explanation:

Assume the following :

a = average speed traveled on level road

(a - 20) = average speed traveled on winding road

Recall:

Distance = speed × time

Total distance traveled :

Level road distance + winding road distance = 252 miles

3a + 3(a - 20) = 252

3a + 3a - 60 = 252

6a = 252 + 60

6a = 312

a = 52 mph on a level triad

User Arowell
by
3.7k points
6 votes

Answer:

65 mph on level road

Explanation:

Set b as average speed on the level road and (b-20) = average speed on the winding road

Distance = speed * time

Level Road distance + winding road dististance = 285 miles

Substituting b and (b-20), we have,

3b + 2(b-20) = 285

3b + 2b - 40 = 285

5b = 285 + 40

5b = 325

b= 325/5

b = 65 mph on level road

User Joshua Hysong
by
4.7k points