The railway connects two towns. Can you figure out how far apart they are? I. The postal train travels at a speed of 12 km/hr faster than an express train. II. A postal train travels the same distance in 40 minutes less time than an express train.
A. I alone sufficient while II alone not sufficient to answer
B. II alone sufficient while I alone not sufficient to answer
C. Either I or II alone sufficient to answer
D. Both I and II are not sufficient to answer
Answer:D
The railway connects two towns. Can you figure out how far apart they are? I. The postal train travels at a speed of 12 km/hr faster than an express train. II. A postal train travels the same distance in 40 minutes less time than an express train.
A. I alone sufficient while II alone not sufficient to answer B. II alone sufficient while I alone not sufficient to answer C. Either I or II alone sufficient to answer D. Both I and II are not sufficient to answer
Explanation: Allow for a distance of x kilometres between the two stations.I. Then the postal train's speed is (y + 12) km/hr.II. 40/60 = x/y - x/(y + 12).As a result, even when I and II are added together, they do not equal x.