Question

In each question below are given two or three statements followed by two conclusions numbered I and II. You have to take the given statements to be true even if they seem to be at variance with commonly known facts and then decide which of the given conclusions logically follows from the given statements, disregarding commonly known facts. Give answer
Statements: Some balls are locks.
All locks are keys.
Some doors are keys.
Conclusions: I. All doors being keys is a possibility.
II. Some balls are keys.

• A. if only conclusion I follows.
• B. if only conclusion II follows.
• C. if either conclusion I or II follows.
• D. if neither conclusion I nor II follows.
• E. if both conclusions I and II follow.

Answer 1

The correct option is B if only conclusion II follows.

• Some balls are locks. Means region representing keys and region representing locks have a common portion.
• All locks are keys. Means region representing locks is completely inside keys.
• Some doors are keys. Means region representing keys and region representing doors have a common portion.

1. All doors being keys is a possibility. Wrong since according to the third statement only a part of doors, is keys.
2. Some balls are keys. Right because as we can see in the diagram, there is definitely a portion common in both balls and keys.