The question consists of two statements numbered “I and II” given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. Determine the speed of Train
X. Statement I: Train 'X' can cross a tree in 9 seconds. Statement II: Train 'X' can cross a platform 300-meter long in 21 seconds.

ATQ, Statement I: Let the length of Train X = x meter So the speed of Train X = x/9 m/s We can’t find the speed of Train X. So, data in statement I alone is not sufficient to answer the question. Statement II: Let the length of Train X = x meter So the speed of Train X = (x + 300)/21 m/s We can’t find the speed of Train X. So, data in statement II alone is not sufficient to answer the question. Combining statements I and II: x/9 = (x + 300)/21 7x = 3x + 900 4x = 900 x = 225 So the speed of Train X = 225/9 = 25 m/s So, data in statement I and statement II together are necessary to answer the question.