20 minutes( 0.3333 hours) after they leave the station will they be 50 km apart, if the Two trains on opposite tracks leave the same station at the same time. One train travels at an average speed of 80 km/hr and the other travels at an average speed of 70 km/hr.
Explanation:
The given is,
One train travels at an average speed of 80 km/hr
The other travels at an average speed of 70 km/hr
Step:1
Formula to calculate the distance traveled by two trains,
Distance traveled by two trains = (Rate of speed of train one +
Rate of speed of other train) × Time
From the given the above equation becomes,
Let, h = Time taken to each the distance
50 = ( 80 + 70 ) h
50 = (150) h
= 0.3333 hours
= ( 0.333 × 60 ) ( ∵ 1 hr = 60 minutes )
h = 20 minutes
Step:2
Check for solution,
From equation (1),
50 = ( 80+70 ) (0.3333)
50 = (150)(0.3333)
50 = 50
Result:
20 minutes( 0.3333 hours) after they leave the station will they be 50 km apart.