Assume the statements are true.
Statements: All gates are walls. No gate is a roof.
Conclusions:
I. Some walls are not roofs.
II. Some roofs are not walls.

Only I followsCorrect answerYour answerOnly II followsCorrect answerYour answerNeither I nor II followsCorrect answerYour answerBoth I and II followCorrect answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer A

Correct answer: A

Gates exist, every gate is a wall, and no gate is a roof. So those walls (the gates) are not roofs: I follows.
Roofs could all sit inside the wall circle, in the part that holds no gates. The statements still hold, so II is not definite.
Only I follows.

Worth noting

With a shared subject ('All G are W', 'No G is R'), the definite conclusion is 'Some W are not R'. Reversing it gives II, which is the trap.

Concept: Shared subject: All + No gives Some … not
Typical timeTypical: 110 s
Your timeYours: —

The rule this testsTwo statements

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Ten questions from Syllogisms, at your own pace.

Assume the statements are true.Statements: All gates are walls. No gate is a roof.Conclusions:I. Some walls are not roofs.II. Some roofs are not walls.

Explanation

Assume the statements are true.
Statements: All gates are walls. No gate is a roof.
Conclusions:
I. Some walls are not roofs.
II. Some roofs are not walls.