Two stations, A and B are 100 km apart on a straight line. One train starts from A at 7 A.M. and travels towards B at a speed of 20 km/h. Another train starts from B at 8 A.M. and travels towards A at a speed of 25 km/h. At what time they will meet?

Correct option is D

Given:

Distance between A and B = 100km

Train starts from A at 7:00AM at 20km/hr

Another train starts from B at 8:00AM at 25km/hr

Formula Used:

​$$Time = \frac{Distance}{Speed}$$​​

Solution:

Distance travelled by train one from 7:00AM to 8:00AM:

Time = 1hour

=$$20km/hr \times 1 = 20km$$​​

Distance left when another train starts from station B = 100 - 20 = 80km

Relative speed when both train A and B are moving towards each other = 20 + 25 = 45km/hr

Time taken to meet =$$\frac{80}{45} = \frac{16}{9}hour = 1\frac{7}{9}hour$$​​

Time in minutes = $$1 hour and \frac{7}{9} \times 60 = 1\ hour\ and \ 46.6minutes$$​​

Time from 8:00AM + 1 hour 47 minutes = 9 : 47min