(136–138): Each question is followed by two statement I & II. You have to…
2025
(136–138): Each question is followed by two statement I & II. You have to determine which statement (s) is/are necessary/sufficient to answer the question and mark answer accordingly
Q136. What is speed of train?
I. The train can cross 100 m long platform in 10 sec & a trees in 5 sec.
II. The train can cross another train of same length coming from opposite direction at same speed in 20 sec.
- A.
Only statement II alone is sufficient to answer
- B.
Either statement I or statement II alone is sufficient to answer.
- C.
Both statement I & II together are necessary to answer.
- D.
Only statement I alone is sufficient to answer.
- E.
Neither statement I nor statement II is sufficient to answer.
Attempted by 4 students.
Show answer & explanation
Correct answer: D
Statement I is sufficient: crossing a tree gives L/v = 5, and crossing a 100 m platform gives (L + 100)/v = 10, so speed can be found.
Statement II gives only a relation between length and speed for two equal trains and is not sufficient by itself.
Therefore, only statement I alone is sufficient.