Logical Reasoning - Logical Deduction - Discussion

Discussion Forum : Logical Deduction - Section 3 (Q.No. 17)
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.


17.

Statements: All snakes are trees. Some trees are roads. All roads are mountains.

Conclusions:

  1. Some mountains are snakes.
  2. Some roads are snakes.
  3. Some mountains are trees.

Only I follows
Only II follows
Only III follows
Both I and II follow
None follows
Answer: Option
Explanation:

All snakes are trees. Some trees are roads.

Since the middle term is not distributed even once in the premises, so no definite conclusion follows.

Some trees are roads. All roads are mountains.

Since one premise is particular, the conclusion must be particular and should not contain the middle term. So, it follows that 'Some trees are mountains'. III is the converse of this conclusion and so it holds.

All snakes are trees. Some trees are mountains.

Since the middle term is not distributed even once in the premises, so no definite conclusion follows.

Discussion:
1 comments Page 1 of 1.

Vishal said:   8 years ago
Why conclusion III is right?

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