Question

Places A and B are 80km apart from each other on a highway.A car starts from A and another from B at the same time.If they move in the same direction they meet in 8h and if they move towards each other they meet in 1h 20min.Find the speed of the car
I need it step by step explaination

Answer 1

As; speed = distance / time
And distance = 80 km nd time = 8h in first case
So speed = 80 / 8 = 10 km/h
If u want the answer in m/s then multiply the answer with 5/18 that is 10 * 5 / 18= 25 / 9
In second case ; d= 80 km nd t = 1h 20 min firstly convert 20 min into h i. e. 20/60 = 1/3 h
So ; s= d / t = 80 / 1*1/3 = 80 *3=240 km /h
With same method convert it into m/s

Answer 2

Answer:

Speed of Car A  and B are 35 km / hr and 25 km / hr respectively.

Step-by-step explanation:

Let the speed of car at A is x km / hr and at B is y km / hr

Case 1.

8 x - 8 y = 80

x - y = 10

x = 10 + y ... ( i )

Case 2.

4 / 3 x + 4 / 3 y = 80

x + y = 60

x = 60 - y ... ( ii )

From ( i )  and  ( ii )

10 + y = 60 - y

y = 25

Putting value of y in ( i )

x = 10 + 25

x = 35 .