Using Quadratic Formula to solve Quadratic Equations
10. An express train takes 1 hour less than a passenger train to travel 132 km between Mysore and Bangalore (without taking into consideration the time they stop at intermediate stations). If, the average speed of the express train is 11 km/h more than that of the passenger train, find the average speed of two trains.
Let average speed of passenger train = km/h
Let average speed of express train = km/h
Time taken by passenger train to cover km = hours
Time taken by express train to cover km = hours
According to the given condition, we have
Comparing equation with general quadratic equation , we get and .
Applying Quadratic Formula , we get
We discard because speed cannot be in negative.
Therefore, speed of passenger train = km/h
And, speed of express train = km/h