Which of the following statements are logically equivalent ? Choose the correct answer from the options given below :

1.Some non-sedans are cars

2.Some cars are not non-sedans

3.Some cars are sedans

4.Some sedans are cars

A2, 3 & 4 only ✓ Correct

B1 & 2 only

C1, 2 & 3 only

D1, 3 & 4 only

Correct answer: (A) 2, 3 & 4 only

Explanation

Statements 2, 3 and 4 are logically equivalent.

Take "Some cars are sedans" as the base particular affirmative.

Its obverse is "Some cars are not non-sedans", which is Statement 2.

Its converse, since a particular affirmative converts simply, is "Some sedans are cars", which is Statement 4.

Obversion and simple conversion preserve truth, so these three say the same thing.

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