Instructions

In each question below are given three statements followed by four conclusions numbered I, II, III and IV. You have to take the three given statements to be true even if they seem to be at variance from commonly known facts. Read all the conclusions and then decide which of the given conclusions logically follows from the three given statements, disregarding commonly known facts.

Question 94

# Statements: Some doors are windows. All windows are black. Some black are brown.Conclusions:I. Some windows are brown.II. All doors are black.III. Some doors are black.IV. No window is brown.

Solution

We know: Some doors are windows. All windows are black. Some black are brown.

We shall now test each option by negating them with a possible scenario, and the one that holds true for every scenario shall be a valid conclusion.

1 and 4. Some windows are brown, and no windows are brown. It is clear from the given information that there can be a possibility of windows overlapping with brown as all windows are black and some black are brown. However, we cannot be sure that some windows will fall under brown. Hence, one of the two conclusions shall definitely be true.

2. All doors are black: We only know that some doors are windows, that in turn, are black. However, we cannot say for sure that all doors can be classified as windows for them to be black. Hence, an invalid conclusion.

3. Some doors are black: It is known that some doors are windows, and all windows are black. Hence, the doors that are windows shall also be black. This is a valid conclusion.