Places A and B are 100 km apart on a highway. One car starts form A an

1.	Places A and B are 100 km apart on a highway. One car starts form A and another from B at the same time. If the cars travel in the same direction at different speeds, they meet in 5 hours. If they travel towards each other, they meet in 1 hour. What are the speeds of two cars?
Answer» Let the speed of car from A be ‘a’ and of car from B be ‘b’ Speed = distance/time Relative speed of cars when moving in same direction = a + b Relative speed of cars when moving in opposite direction = a – b Given, Places A and B are 100 km apart on a highway. One car starts from A and another from B at the same time. If the cars travel in the same direction at different speeds, they meet in 5 hours. If they travel towards each other, they meet in 1 hour ⇒ a – b = 100/5 = 20 (1) Also, a + b = 100/1 = 100 (2) Adding (1) and (2) a - b + a + b = 20 + 100 ⇒ 2a = 120 ⇒ a = 60 km/hr Putting value of a in (1) we get, Thus, b = 60 – 20 = 40 km/hr Speed of two cars are 60 km/h and 40 km/h

Places A and B are 100 km apart on a highway. One car starts form A and another from B at the same time. If the cars travel in the same direction at different speeds, they meet in 5 hours. If they travel towards each other, they meet in 1 hour. What are the speeds of two cars?

Answer»

Let the speed of car from A be ‘a’ and of car from B be ‘b’

Speed = distance/time

Relative speed of cars when moving in same direction = a + b

Relative speed of cars when moving in opposite direction = a – b

Given,

Places A and B are 100 km apart on a highway.

One car starts from A and another from B at the same time.

If the cars travel in the same direction at different speeds, they meet in 5 hours.

If they travel towards each other, they meet in 1 hour

⇒ a – b = 100/5 = 20 (1)

Also,

a + b = 100/1 = 100 (2)

Adding (1) and (2)

a - b + a + b = 20 + 100

⇒ 2a = 120

⇒ a = 60 km/hr

Putting value of a in (1) we get,

Thus,

b = 60 – 20 = 40 km/hr

Speed of two cars are 60 km/h and 40 km/h