RRB Group-D Model Paper 12 with answers for online practice

Given:
The speed of the auto-rickshaw = 28 km/h
In starting the person is 70 meters ahead of auto-rickshaw.
The person is 110 meters behind after 30 seconds
Concept used:
When we convert speed into km/h from m/sec we multiply by 18/5.
Formula used:
Relative speed = Total distance/Total time
Calculation:
After 30 second, the total distance between them = 70 + 110 = 180 m.
Now the relative speed = Total distance/Total time = 180/30 = 6 m/sec
Then the relative speed in km/h = 6 × (18/5) = 21.6 km/h
Now relative speed = speed of auto rickshaw – speed of person
⇒ 21.6 = 28 – speed of person
⇒ speed of person = 6.4 km/h
∴ The speed of person is 6.4 km/h.