Question

it's the question of quantitative aptitude plz explain ​

Answer 1

Answer:

20 minutes

Step-by-step explanation:

distance between Hyderabad and Nalgonda is 100km

Train X starts at 5:30am towards Nalgonda,Train Y starts at 6:00 towards Hyderabad..hence both travel in opposite direction..

Mr Shah realises both are on same track at 6:30am..by the time he realises,Train X travelled for 1hr at 50kmph..hence it travelled 50km from Hyderabad towards Nalgonda,Train Y travelled for half an hour at 40kmph..hence it travelled 20km from Nalgonda towards hyderabad..

[40=distance/(1/2),distance is 20km]

now distance between both trains is 100-(50+20)=30km

This 30km distance is covered by both trains from either end in opposite direction..

relative velocity =50+40=90

total distance between trains is 30km

time taken to meet both trains is

time=distance/relative velocity

time=30/90

time=1/3hr

time=(1/3)×60

time=20minutes

hence Mr Shah has 20minutes time ti avert the accident