Logical Reasoning - Logical Problems - Discussion

Discussion Forum : Logical Problems - Type 4 (Q.No. 4)
Directions to Solve
The logic problems in this set present you with three true statements: Fact 1, Fact 2, and Fact 3. Then, you are given three more statements (labeled I, II, and III), and you must determine which of these, if any, is also a fact. One or two of the statements could be true; all of the statements could be true; or none of the statements could be true. Choose your answer based solely on the information given in the first three facts.

4.
 Fact 1: All chickens are birds. Fact 2: Some chickens are hens. Fact 3: Female birds lay eggs.
If the first three statements are facts, which of the following statements must also be a fact?
 I: All birds lay eggs. II: Some Hens are birds. III: Some chickens are not hens.
I only
II only
II and III only
None of the statements is a known fact.
Explanation:
The first statement cannot be true because only female birds lay eggs. Statement II is true because some hens are chickens and all chickens are birds. Statement III is also true because if only some chickens are hens, then some must not be hens.
Discussion:
18 comments Page 1 of 2.

Aditya Senapati said:   4 years ago
"Some chickens are not hens" can not be implied to be correct or incorrect. Because we only know that "some chickens are hens" but we have no idea about rest of the chickens. Hence only conclusion II is correct.
(1)

Manjari said:   6 years ago
I think 2 is the correct answer.

Jumanji said:   6 years ago
Earlier you talked about affirmative and negative sentences.

As in this question no negative sentence hence option 3 is wrong.

Answer should be option 2 only.

Mauleka Jain said:   7 years ago
I think the only fact which is correct is III.
(1)

Himanshi r said:   7 years ago
Option B is correct.

You cannot convert some to some not because if you did that means From a single statement you are concluding many.

For ex: if you say all chickens are hens, we can also say that some chicken are hens which is true and it's converse some hens are chickens is also true.

Now,

According to your rule, some chicken are hens can also be said some chicken are not hens which is not possible since you cannot converse it plus there will be number of conclusions from a single statement.

RSR said:   8 years ago
Only 2 is correct.

Goulal said:   8 years ago
Can anybody tell me the Logic and Reasoning?

Poki said:   8 years ago

Daniel said:   9 years ago
Statement 1: Incorrect because all birds refers to both male and female birds and only female birds lay eggs.

Statement 2: Incorrect because of common sense and basic observation. No one has ever seen a hen that doesn't fall into anything other than the bird category in the animal kingdom.

Statement 3: Correct because of basic observation again.

Nirali said:   9 years ago
Only II is correct as we can never derive about NOT from the facts.