Discussion Forum



1)

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

Statements:  Some towels are brushes. No brush is soap. All soaps are rats.

Conclusions : : I. Some rats are brushes. II. No rat is brush. III Some towels are soaps


A) None follows

B) Only either I or II follows

C) Only II follows

D) Only I and III follows

E) None of these

Answer:

Option B

Explanation:

Some towels are brushes. No brush is soap.

Since one premise is particular and the other negative, the conclusion must be particular negative (O-type) and should not contain the middle term. So, it follows that 'Some towels are not soaps'.

No brush is soap. All soaps are rats.

Since the middle term is distributed twice, the conclusion must be particular. Since one premise is negative, the conclusion must be negative. So, it follows that 'Some brushes are not rats'. Since I and II involve the same terms and form a complementary pair, so either I or II follows.