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A train travels 315 km in the same time that a car travels 265 km. If the train travels on average 20 km/h faster than the car, find the average speed of the car and the time taken to travel 265 km.

2 Answers

4 votes

Final answer:

The average speed of the car is 106 km/h, and it takes 2.5 hours to travel 265 km. The train travels at an average speed of 126 km/h.

Step-by-step explanation:

To find the average speed of the car and the time taken to travel 265 km, we can use the relationship between distance, speed, and time, which is expressed as speed = distance/time.

Let V be the average speed of the car. Then, the average speed of the train will be V + 20 km/h. Since both travel the same time (t), we can set up the following equations:

  • Speed of car: V
  • Speed of train: V + 20 km/h
  • Distance traveled by car: 265 km
  • Distance traveled by train: 315 km

Therefore, we can write two equations based on the definition of speed:

  1. 265 km = V * t
  2. 315 km = (V + 20) * t

Next, we can solve these equations simultaneously. Divide the distance by the speed for each vehicle to find the time:

  • t = 265 km / V
  • t = 315 km / (V + 20)

Since the time t is the same for both, we can equate these two expressions:

265 / V = 315 / (V + 20)

Now we cross-multiply:

265 * (V + 20) = 315 * V

265V + 5300 = 315V

50V = 5300

V = 5300 / 50

V = 106 km/h

This is the average speed of the car. The train, therefore, travels at 106 + 20 = 126 km/h.

To find the time, use the speed of the car:

t = 265 km / 106 km/h = 2.5 hours

This is the time taken to travel 265 km by car.

User Tchami
by
7.2k points
3 votes

Answer: 106 km/h,2.5 hr

Step-by-step explanation:

Given

The train travels 315 km in the same time car travels 265 km

The average speed of the train is 20 kmph faster than car

Suppose, speed of the car is v and it travels 265 km in t hours


\therefore (315)/(v+20)=(265)/(v)\\\\\Rightarrow 315v=265\left (v+20\right)\\\\\Rightarrow 315v=265v+5300\\\Rightarrow 50v=5300\\\Rightarrow v=106\ km/h

Time taken to travel is


\Rightarrow t=(265)/(106)}\\\\\Rightarrow t=2.5\ h

User Alexey Shiklomanov
by
6.8k points