a party of hunter made a trip of 720km to a hunting lodge in 9 hours.they travelled 6 hours on a paved highway and the reminder of the time on a pasture road. If the average speed through the pasture was 30 km/h less than that on the highway, find the average speed and the distance travelled on each part of the trip?
Answers
• Average speed on the paved highway is 90 km/h
• Average speed on the pasture road is 60 km/h
• Distance travelled in 1st part = 540 km
• Distance travelled in 2nd part = 180 km
Step-by-step explanation:
Given that, 720 km path is travelled in 9 hours; in which the paved highway is travelled for 6 hours and the pasture road is travelled for (9 - 6) hours = 3 hours.
Let, the average speed on the paved highway is x km/h.
Then by the given condition, the average speed on the pasture road is (x - 30) km/h
∴ in 6 hours, they travel 6x km on the paved highway and in 3 hours, they travel {3 (x - 30)} = (3x - 90) km on the pasture road.
By the given condition,
6x + (3x - 90) = 720
or, 6x + 3x - 90 = 720
or, 9x = 720 + 90 = 810
or, x = 90
∴ the average speed on the paved highway is 90 km/h
∴ the average speed on the pasture road is
= (90 - 30) km/h
= 60 km/h
∴ in the first part, for 6 hours, they travelled (6 × 90) km = 540 km and in the second part, for 3 hours, they travelled {3 (90 - 30)} km = 180 km.
Answer:
the average speed and the distance traveled on each part of the trip is given by:
Paved highway: Distance = 540 km
Speed = 90 km/h
Pasture road: Distance = 180 km
Speed = 60 km/h
Step-by-step explanation:
Let the distance traveled on the paved highway be x km.
The distance traveled on the pastured road is therefore = (720 - x) km
The time taken on the pastured road is = 9 - 6 = 3 hours
Now, speed = distance/time
The average speed through:
- the pasture = (720 - x)/3
- the paved highway = x/6
We have that, the average speed through the pastured road was 30 km/h less than that of the paved highway.
Writing this down we have:
(720 - x)/3 = x/6 - 30
6(720 - x) = 3x + 30 × 6 × 3
4320 - 6x = 3x - 540
9x = 4860
x = 540 km
The speed through the pasture = (720 - 540)/3 = 60 km/h
The speed through the paved highway = 540/6 = 90 km/h
The distance traveled on the paved highway = 540 km
Pasture road = 180 km