Question

0.9
Two trains started at 7AM from the same point. The first train travelled north at a speed of 80km/h
second train travelled south at a speed of 100km/h. The time at which they were 540km apart is
(A) 9 (B) 10
(C) 11 (D) 11.30​

Answer 1

Answer:

A) 9 is the answer you need

Answer 2

Answer:

After travelling for 3 hours , Both the train will be apart 540 km at 10 AM

Step-by-step explanation:

Given as :

The speed of train travelling north direction = S = 80 km/h

The speed of train travelling south direction = s = 100 km/h

The distance between both trains = D = 540 km apart

Let The time taken by both train to move 540 km apart = T hours

Both Train start moving away at 7 AM

According to question

∵ Distance = Speed × Time

As both train moving away from them

So, The speed of both trains will be = S - s

Now, D = (s + S) × T

Or, 540 km = (100 + 80) km/h × T

Or, 540 = 180 × T

∴  T = $\dfrac{540}{180}$

i.e T = 3 hours

So, The time taken by both train to move 540 km apart = T = 3 hours

Now, Since both train start at 7 A.M

So, After travelling for 3 hours , Both the train will be apart at 540 km at 7 AM + 3 hours

i.e  After travelling for 3 hours , Both the train will be apart at 540 km at = 10 AM

Hence,  After travelling for 3 hours , Both the train will be apart at 540 km at 10 AM . Answer