Two trains which are 80 kilometerse apart start to travel at

Two trains which are 80 kilometerse apart start to travel at the same time toward each other. If the first travels at the rate of 55 kph and the second one at 45 kph, after how many hours will they meet?

Solution

In these type of questions - Think Logically that after 1 hour what will happen.
Since both are moving towards each other they are together covering the distance between them from both the ends.
Let us assume that one train is at point A and other at point B
A ----------------------------- B
<----- 80 km -------------->
The first train starting from A travels at the speed of 55 kph
i:e it travels 55 km in one hour
The second train starting from B travels at the speed of 45 kph
i:e it travels 45 km in one hour
So in one hour together they will cover Distance = 55 + 45 = 100 km
i:e Speed is 100 kph
And the distance to be covered (between them) is 80 km
So Finding Time taken --
Using the formula Speed = Distance/Time
Time = Distance /Speed
Time = 80/100
Time = 4/5 hour
TIme = (4/5)*60 minutes = 48 minutes