Question

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 station). If the average speed of the express train is 11 km per hour more than that of the passenger train, find the average speed of the two trains. ​

Answer 1

Answer:44 km/hr

Step-by-step explanation::

speed of passenger train=xkm/hr

speed of express train =(x+11)km/hr

time taken by passenger train=132x=132x

time taken by express train=132x+11=132x+11

acc to question

132x+11=132x−1

132[1x−1x+11]=1

132[x+11−xx(x+11)]=1

132⋅11=x(x+11)

x2+11x−1452=0

x2+44x−3x−1452=0

x(x+44)−33(x+44)=0

(x−33)(x+44)=0

x=33,−44

x=-44 cant be possible as x cant be zero

so, x=33 & x+11=44 km/hr

Answer 2

Answer:

Let the speed of passenger train be x km/h.

So ,

Speed of Express will be = X+11 km/h

Now , Distance is 132km.

We know that ,

$time = \frac{distance}{speed}$

According to question ,

$\frac{132}{x} - \frac{132}{x + 11} = 1$

On Multiplying the equation by X(X+11) , we get ;

$132(x + 11) - 132x = (x + 11)x$

$1452 = {x}^{2} + 11x$

${x}^{2} + 11x - 1452 = 0$

${x}^{2} + 44x - 33x - 1452 = 0$

$x(x + 44) - 33(x + 44) = 0$

$(x + 44)(x - 33)$

So ,

X = 33 , -44

Speed can't be negative . so , X = 33

Thus , speed of passenger is 33km/h

and speed of Express is 33+10 = 44km/h

Hope it helps you :)