Question

Two trains start from P and Q respectively and travel towards each other at a speed of 50km/h and 40km/h.By the time they meet,the first train has travelled 100km more than the second.The distance between P and Q is:(a) 500km (b)630km (c)660km (d)900km?

Answer 1

let time taken =x h
distance covered by Q= 40x km
distance by P=50x
50x-40x=100
x=10
hence distance between P&Q= 40x+50x=900km =Ans

Answer 2

Answer:

Distance between the points P and Q is 900 km.

Step-by-step explanation:

Let the distance traveled by train that starts from point P is x km and distance traveled by train that starts from point Q is y km by the time they meet.

Distance between points P and Q = (x + y) km

Time taken first train starting from P to travel x km = $\frac{\text{Distance}}{\text{Speed}}$

= $\frac{x}{50}$ hours

Time taken by the second train starting from point Q = $\frac{y}{40}$ hours

Difference between the distances traveled by the two trains = 100 km

x - y = 100 --------(1)

These trains travel for the same time,

$\frac{x}{50}=\frac{y}{40}$

x = $\frac{5y}{4}$ ------(2)

Now by replacing the value of x in equation (1) from equation (2)

$\frac{5y}{4}-y=100$

$\frac{y}{4}=100$

y = 400 km

from equation (1),

x - 400 =100

x = 100 + 400

x = 500 km

Now distance between points P and Q = 400 + 500 = 900 kms

Therefore, distance between P and Q is 900 kms.

Option (d) is the answer.

Learn more on speed, distance and time from https://brainly.in/question/5108710