Question

Average speed of Car 1 = 55 mph. Average speed of Car 2 = 70 mph. Time elapsed between start of Car 1 and start of Car 2 = 4 minutes. How long before Car 2 overtakes Car 1? hour =

Answer 1

Average speed of Car 1 = 55 mph. Average speed of Car 2 = 70 mph. Time elapsed between start of Car 1 and start of Car 2 = 4 minutes. How long before Car 2 overtakes Car 1? hour = 0.24 hours

Answer 2

Explanation:

Alright, lets get started.

Suppose car 2 overtakes car 1 at distance d in t hrs after car 1 moves.

So, distance covered by car 1 in t hrs will be :

`distance = speed*time`

`d=55*t = 55t`

distance covered by car 2 will take 4 minutes less that car 1, so time will be

`(t-(4)/(60))=(t-0.067)`

So, distance covered by car 2 will be:

`d = 70*(t-0.067) = 70t - 4.69`

Both distance will be same for overtaking, so

`55t = 70t-4.69`

`15t = 4.69`

`t =0.31 hrs`

It will take 0.31 hrs to overtake car 1 : Answer

Hope it will help :)