Saturday, August 30, 2014

distance and speed

Two trains leave the railway station at the same time. One train is travelling due north and the other due east. The first train is 5 km/hr faster than the second train. If after 2 hours, the trains are 50 km apart, what is the speed of each train?



Answer:
if speed of one train is x, the speed of other train is x + 5
so, the distance travelled by each train in 2 hours = 2x and 2(x + 5)

now, given (2x)2 + {2(x + 5)}2 = 502
So x = 15 km/hr (ignore negative value)
so, speed of the trains are 15 and 20 km/hr


No comments:

Post a Comment