A man travels 400 km partly by train and partly by car. If he covers 2

1.	A man travels 400 km partly by train and partly by car. If he covers 240 km by train and rest by car, it takes 6 hours. But if he travels 180 km by train and rest by car, he takes 15 minutes lesser. Find the speed of the train and that of the car.
Answer» Answer: Train = 60 km/hr Car = 80 km/hr Step-by-step explanation: Given that, A man travels 400 km. He travels the distance by train and car. To find the speed. Let the speed of train be x km/hr and that of car is y km/hr. We know that, Speed = Distance/Time => Time = Distance/Speed Now, in FIRST case, we have, Distance by train = 240 km Distance by car = (400-240) = 160 km Time taken = 6 hr Therefore, we have, => 240/x + 160/y = 6 ......(1) Now, in SECOND case, we have, Distance by train = 180 km Distance by car = (400-180) = 220 km Time taken = 6 - 15/60 = 6-¼ = 23/4 hr Therefore, we will get, => 180/x + 220/y = 23/4 ......(2) Multiplying eqn (1) with 3 and eqn (2) with 4 and subtracting, we get, => 480/y - 880/y = 18 - 23 => (880-480)/y = 23 - 18 => 400/y = 5 => y = 400/5 => y = 80 SUBSTITUTING this value in eqn (1), we get, => 240/x + 160/80 = 6 => 240/x = 6 - 2 => x = 240/4 => x = 60 Hence, the speed of the train and that of the car is 60 km/hr and 80 km/hr respectively.

A man travels 400 km partly by train and partly by car. If he covers 240 km by train and rest by car, it takes 6 hours. But if he travels 180 km by train and rest by car, he takes 15 minutes lesser. Find the speed of the train and that of the car.

Answer»

Answer:

Train = 60 km/hr

Car = 80 km/hr

Step-by-step explanation:

Given that,

A man travels 400 km.

He travels the distance by train and car.

To find the speed.

Let the speed of train be x km/hr and that of car is y km/hr.

We know that,

Speed = Distance/Time

=> Time = Distance/Speed

Now, in FIRST case, we have,

Distance by train = 240 km

Distance by car = (400-240) = 160 km

Time taken = 6 hr

Therefore, we have,

=> 240/x + 160/y = 6 ......(1)

Now, in SECOND case, we have,

Distance by train = 180 km

Distance by car = (400-180) = 220 km

Time taken = 6 - 15/60 = 6-¼ = 23/4 hr

Therefore, we will get,

=> 180/x + 220/y = 23/4 ......(2)

Multiplying eqn (1) with 3 and eqn (2) with 4 and subtracting, we get,

=> 480/y - 880/y = 18 - 23

=> (880-480)/y = 23 - 18

=> 400/y = 5

=> y = 400/5

=> y = 80

SUBSTITUTING this value in eqn (1), we get,

=> 240/x + 160/80 = 6

=> 240/x = 6 - 2

=> x = 240/4

=> x = 60

Hence, the speed of the train and that of the car is 60 km/hr and 80 km/hr respectively.