Logical Reasoning - Logical Deduction - Discussion

Discussion Forum : Logical Deduction - Section 3 (Q.No. 2)
Directions to Solve

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


2.

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

Conclusions:

  1. Some rats are brushes.
  2. No rat is brush.
  3. Some towels are soaps.

None follows
Only either I or II follows
Only II follows
Only I and III follow
None of these
Answer: Option
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.

Discussion:
13 comments Page 1 of 2.

Eswar said:   2 years ago
According to the income-expenditure method,

I think 1 and 3 follow.

VIDYA U K said:   2 years ago
Only 2 follows should be the right answer according to venn diagrams.

Young T said:   6 years ago
Only II follows. Rats are not members of brushes using the Venn diagram rule, in the same vein, towels and soaps have nothing in common.

Ravi said:   6 years ago
I think it is only 2 follows.

Sathish said:   7 years ago
Sir, you said that no term can be distributed in the conclusion unless it is distributed in the premises. From the premises "no brush is soap. All soaps are rats". "Some brushes are not rats. " Conclusion is drawn. But the term brushes is distributed in the given premise and the term rats is not distributed in the given premise but brushes is not distributed and rats is distributed in the conclusion.

Could you please clarify my doubt?

Alok Chahande said:   7 years ago
First statement does follow.

No brush is a soap, all soaps are rats. Assume there are 10B, 15S and 20 R, none of the 10 B are S. Whereas all 15S are R but the remaining Rats can be anything. There is no statement stopping rest of the rats from being brushes (5R!= Soaps).

Sumanth G said:   7 years ago
I think only 2 follows.

3 is following in only 1 out of 2 cases.

Aakash said:   7 years ago
I think 2 and 3 follows.

Rahul said:   7 years ago
Here, Either 1, 2 or 3 follows.

Some rats may be brushes or no rat is the brush.
And some towels may be soap.

Pratiksha said:   8 years ago
Can someone please explain how I & II follows?

I think only II follows.


Post your comments here:

Your comments will be displayed after verification.