Given below are two statement, followed by two conclusion, I and II. You have to consider the statement to be true even if they seem to be at variance from commonly known facts. You have to decide which of the given conclusions, if any, follow(s) from the given statements. Statement 1: No quadrilaterals are polygons. Statement 2: All polygons are rhombuses. Conclusion I: Some rhombuses are quadrilaterals.
Only conclusion II follows
Let's carefully analyze the given statements and conclusions in this syllogism problem involving geometric shapes like quadrilaterals, polygons, and rhombuses.
We are given two statements:
We must assume these statements are true, even if they contradict commonly known facts about geometry.
In terms of set relationships:
We need to determine which of the following conclusions logically follow from the given statements:
This conclusion claims that there is at least one element that is both a rhombus and a quadrilateral, meaning the intersection of Rhombuses (R) and Quadrilaterals (Q) is not empty: \(R \cap Q \neq \emptyset\).
From the statements, we know:
Since all polygons are rhombuses, the set of polygons is a part of the set of rhombuses. Statement 1 tells us that quadrilaterals have nothing in common with polygons.
Consider the possibility that the set of rhombuses (R) is exactly the same as the set of polygons (P). In this case, Statement 2 (All polygons are rhombuses) would be true. Statement 1 (No quadrilaterals are polygons) would also be true. Now, check Conclusion I: "Some rhombuses are quadrilaterals". If R = P, this means "Some polygons are quadrilaterals". But Statement 1 says "No quadrilaterals are polygons", which implies "No polygons are quadrilaterals" and therefore "Some polygons are quadrilaterals" is false.
Since we found a scenario where the statements are true but Conclusion I is false (R = P is a possible scenario under Statement 2), Conclusion I does not necessarily follow from the statements. The statements do not guarantee an overlap between rhombuses and quadrilaterals.
This conclusion claims that there is at least one element that is both a rhombus and a polygon, meaning the intersection of Rhombuses (R) and Polygons (P) is not empty: \(R \cap P \neq \emptyset\).
Statement 2 says: "All polygons are rhombuses" (\(P \subseteq R\)). This means every element in the set of polygons is also in the set of rhombuses.
In standard syllogistic logic, a universal affirmative statement like "All P are R" implies the existence of P unless explicitly stated otherwise. If there are any polygons (if the set P is not empty), then because all polygons are rhombuses, those polygons are also rhombuses.
Therefore, if the set of polygons is non-empty, there exist elements that are both polygons and rhombuses. This makes the conclusion "Some rhombuses are polygons" (\(R \cap P \neq \emptyset\)) true.
Since the standard interpretation assumes the subject of a universal statement exists, Statement 2 implies the existence of polygons, and thus implies that "Some rhombuses are polygons" follows.
Therefore, only Conclusion II follows.
Let's look at the options:
Based on our analysis, the correct option is the one stating that only conclusion II follows.
| Item | Description | Set Notation |
|---|---|---|
| Statement 1 | No quadrilaterals are polygons. | \(Q \cap P = \emptyset\) |
| Statement 2 | All polygons are rhombuses. | \(P \subseteq R\) |
| Conclusion I | Some rhombuses are quadrilaterals. | \(R \cap Q \neq \emptyset\) |
| Conclusion II | Some rhombuses are polygons. | \(R \cap P \neq \emptyset\) |
This question uses categorical syllogisms, a type of logical argument that applies deductive reasoning to arrive at a conclusion based on two or more propositions that are asserted or assumed to be true. The statements and conclusions relate categories or classes of things.
Types of Categorical Propositions:
In our analysis, Statement 2 (All polygons are rhombuses) is an A-type proposition. Conclusion II (Some rhombuses are polygons) is an I-type proposition. From "All P are R" (A-type), we can logically infer "Some P are R" (I-type) by subalternation (assuming P is not empty). The converse of "Some P are R" is "Some R are P", which is Conclusion II. This is a valid inference.
Statement 1 (No quadrilaterals are polygons) is an E-type proposition. Combined with Statement 2 (All polygons are rhombuses), we saw that Conclusion I (Some rhombuses are quadrilaterals) does not necessarily follow. In fact, the valid conclusion from Statement 1 and 2 is "No quadrilaterals are rhombuses" (E-type in the 4th figure, using P as the middle term: No Q are P, All P are R -> No Q are R, which is equivalent to No R are Q). If "No R are Q" is true, then "Some R are Q" must be false.
Consider the given statements true and decide which of the given conclusion(s) logically follow(s) from the statements.
Statements:
1. All reds are yellows.
2. Some yellow are not greens.
Conclusions:
1. Some yellow are reds
2. All yellow are greens
Consider the given statements to be true and decide which of the conclusions logically follow(s) from the given statements.
Statement:
All fruits are trees. Some trees are birds.
Conclusions:
1. Some birds are trees.
2. Some trees are fruits.
Read the given statements and conclusions carefully. You have to take the given statements to be true even if they seem to be at variance from commonly known facts and decide which conclusion(s) logically follow(s) from the given statements.
Statements:
Some cars are bikes.
All bikes are trucks.
Conclusions:
(I) Some trucks are cars.
(II) All trucks are cars.
Read the given statements and conclusions carefully. You have to take the given statements to be true even if they seem to be at variance from commonly known facts and decide which conclusion(s) logically follow(s) from the given statements.
Statements:
Some gold are silver.
Some silver are diamonds.
Conclusions:
(I) Some diamonds are gold.
(II) Some silver are gold.
Read the given statements and conclusions carefully. You have to take the given statements to be true even if they seem to be at variance from commonly known facts and decide which conclusion(s) logically follow(s) from the given statements.
Statements:
Some bulbs are sands.
All bulbs are candles.
Conclusion:
(I) Some candles are bulbs.
(II) No candle is a sand.
Consider the given statement to be true and decide which of the conclusions logically follows (s) from the statements.
Statements:
Some angels are gods.
All living being are gods.
Conclusions:
1. Some gods are angels.
2. Some living beings are gods.Consider the given statement as true and decide which of the given conclusions can definitely be drawn from the given statements.
Statements:
Dhoni is a good batsman.
Batsman are smart.
Conclusions:
1. All smart people are batsman
2. Dhoni is smart.Consider the given statement to be true and decide which of the given conclusions can definitely be drawn from the given statements.
Statements:
Some lawyers are females. Some females are mothers.
Conclusion:
1. Some mothers are females.
2. Some lawyers are mothers.Consider the given statements to be true and decide which of the given conclusions can definitely be drawn from the statements.
Statements:
All sharks are fish. No fish is a snake.
Conclusions:
1. No snake is a shark.
2. No shark is a snake.Consider the given statement to be true and decide which of the given conclusion(s) logically follow(s) from the statement.
Statement:
Some bugs are birds. All the birds are fruits.
Conclusions:
1. All the fruits are birds.
2. Some of the bugs are fruits.
The statements below are followed by conclusions labeled I, II and III. Assuming that the information in the statements is true, even if it appears to be at variance with generally established facts, decide which conclusion(s) logically and definitely follow(s) from the information given in the statements.
Statements:
All twenty are thirty.
All thirty are forty.
All forty are sixty.
All sixty are seventy.
Conclusions:
I. Some forty are thirty.
II. Some seventy are sixty.
III. No thirty is twenty.The statements below are followed by two conclusions labelled I and II. Assuming that the information in the statements is true, even if it appears to be at variance with generally established facts, decide which conclusion(s) logically and definitely follow(s) from the information given in the statements.
Statements:
All Strong are animals.
Some animals are Tigers.
All Tigers are Sharp.
Conclusions:
I. Some Strong are Sharp.
II. No Strong is Sharp.The statements below are followed by conclusions labelled I, II and III. Assuming that the information in the statements is true, even if it appears to be at variance with generally established facts, decide which conclusion(s) logically and definitely follow(s) from the information given in the statements.Statements:
Some women are weak.
Some weaks are female.
All female are iron.
All iron are gold.Conclusions:
I. Some weaks are iron.
II. Some gold are weaks.
III. Some women are female.
The statements below are followed by two conclusions labeled I and II. Assuming that the information in the statements is true, even if it appears to be at variance with generally established facts, decide which conclusion(s) logically and definitely follow(s) from the information given in the statements.Statements:
Some teaspoons are glasses.
All teddies are teaspoons.
Conclusions:
I. Some teddies are glasses.
II. Some glasses are teddies.
The statements below are followed by two conclusions labeled I and II. Assuming that the information in the statements is true, even if it appears to be at variance with generally Established facts, decide which conclusion(s) logically and definitely follow(s) from the Information, Given in the Statements.
Statements:
All bangles are rings.
Some rings are toys.
Some toys are dolls.
Conclusions:
I. Some rings are bangles.
II. Some dolls are rings.