Two Statements are given followed by two conclusions numbered I and II. Assuming the statements to be true, even if they seem to be at variance with commonly known facts, decide which of the conclusions logically follow(s) from the statements. Statements: Some windows are houses. Some windows are roofs. Conclusions: I. Some roofs are houses. II. Some roofs are windows.
Only conclusion II follows.
Analyzing Statements and Conclusions in Logic
This question asks us to evaluate two statements and determine which of the given conclusions logically follow from them. We must assume the statements are true, even if they don't align with real-world knowledge. This type of problem is common in logical reasoning tests.
Understanding the Given Statements
We are given the following statements:
- Statement 1: Some windows are houses.
- Statement 2: Some windows are roofs.
These statements describe relationships between sets of things: windows, houses, and roofs. The word "Some" indicates that there is at least one element in common between the described sets, but not necessarily all elements.
Evaluating Conclusion I: Some roofs are houses
Conclusion I states: Some roofs are houses.
Let's consider the information provided by the statements:
- Statement 1 tells us there is an overlap between the set of 'windows' and the set of 'houses'.
- Statement 2 tells us there is an overlap between the set of 'windows' and the set of 'roofs'.
The statements establish a relationship between 'windows' and 'houses', and between 'windows' and 'roofs'. However, they do not provide any direct or indirect relationship between 'houses' and 'roofs'. The group of 'some windows' that are 'houses' could be completely different from the group of 'some windows' that are 'roofs'. It is possible that no 'roofs' are 'houses' based *only* on the information given.
Therefore, Conclusion I ("Some roofs are houses") does not logically follow from the given statements.
Evaluating Conclusion II: Some roofs are windows
Conclusion II states: Some roofs are windows.
Let's look at Statement 2 again: Some windows are roofs.
In logic, if a statement says "Some A are B", it implies that "Some B are A". This is because the relationship of "some are" denotes an overlap or intersection between two sets. If there is an overlap where some elements of set A are also in set B, then it necessarily means that some elements of set B are also in set A.
Since Statement 2 says "Some windows are roofs", it logically follows that "Some roofs are windows".
Therefore, Conclusion II ("Some roofs are windows") logically follows from the given statements.
Conclusion
Based on the analysis of each conclusion:
- Conclusion I does not follow.
- Conclusion II follows.
Thus, only conclusion II follows from the given statements.
| Statements | Conclusions | Logically Follows? | Reasoning |
|---|---|---|---|
| Some windows are houses. | I. Some roofs are houses. | No | No direct or indirect link between roofs and houses is established by the statements. |
| Some windows are roofs. | II. Some roofs are windows. | Yes | Follows directly from the premise "Some windows are roofs" (If Some A are B, then Some B are A). |
Revision Table: Syllogism Analysis
| Item | Description |
|---|---|
| Statement 1 | Some windows are houses. |
| Statement 2 | Some windows are roofs. |
| Conclusion I | Some roofs are houses. |
| Conclusion II | Some roofs are windows. |
| Result | Only Conclusion II follows. |
Additional Information: Syllogism Basics
Syllogisms are a form 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.
- Statements are also called premises.
- The goal is to find what *must* be true if the premises are true.
- The word "Some" in logic means "at least one, and possibly all".
- A common logical inference is the conversion of "Some A are B" to "Some B are A". This type of conversion is valid.
- However, converting "All A are B" to "All B are A" is not valid.
- Also, converting "Some A are not B" to "Some B are not A" is not valid.
- It's crucial not to use outside knowledge and rely strictly on the relationships given in the statements.
Important Questions from Miscellaneous
A stone is thrown horizontally from the top of a 20 m high building with a speed of 12 m/s. It hits the ground at a distance R from the building. Taking g = 10 m/s2 and neglecting air resistance will give :
A sphere of volume V is made of a material with lower density than water. While on Earth, it floats on water with its volume f1V (f1 < 1) submerged. On the other hand, on a spaceship accelerating with acceleration a < g (g is the acceleration due to gravity on Earth) in outer space, its submerged volume in water is f2V. Then:
A railway wagon (open at the top) of mass M1 is moving with speed v1 along a straight track. As a result of rain, after some time it gets partially filled with water so that the mass of the wagon becomes M2 and speed becomes v2. Taking the rain to be falling vertically and the water stationery inside the wagon, the relation between the two speeds v1 and v2 is :
Consider the following statements:
1. Distance between the longitudes becomes zero on North Pole and South Pole.
2. Distance between the longitudes is maximum on the Equator.
3. Number of longitudes is more than number of latitudes.
Which of the statements given above is/are correct?
One block of 2⋅0 kg mass is placed on top of another block of 3⋅0 kg mass. The coefficient of static friction between the two blocks is 0⋅2. The bottom block is pulled with a horizontal force F such that both the blocks move together without slipping. Taking acceleration due to gravity as 10 m/s2, the maximum value of the frictional force is :
