Must Be False - LSAT Logical Reasoning
Card 1 of 30
Identify the must-be-false statement: 'No squares are circles.'
Identify the must-be-false statement: 'No squares are circles.'
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Some squares are circles. This contradicts the negative universal by claiming overlap exists.
Some squares are circles. This contradicts the negative universal by claiming overlap exists.
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Identify the false statement: 'If it rains, the ground is wet.'
Identify the false statement: 'If it rains, the ground is wet.'
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It rains and the ground is not wet. This violates the conditional by having the antecedent true but consequent false.
It rains and the ground is not wet. This violates the conditional by having the antecedent true but consequent false.
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Which option must be false if 'No birds are mammals'?
Which option must be false if 'No birds are mammals'?
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Some birds are mammals. This directly contradicts the negative universal statement.
Some birds are mammals. This directly contradicts the negative universal statement.
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Identify the false statement: 'If G, then H.'
Identify the false statement: 'If G, then H.'
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G occurs and H does not occur. This violates the conditional by having G true but H false.
G occurs and H does not occur. This violates the conditional by having G true but H false.
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Which must be false if 'All humans are mortal'?
Which must be false if 'All humans are mortal'?
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Some humans are immortal. This contradicts the universal claim about human mortality.
Some humans are immortal. This contradicts the universal claim about human mortality.
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What does 'must be false' mean in logical reasoning?
What does 'must be false' mean in logical reasoning?
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An option contradicts the given information. This defines the logical relationship where a statement cannot be true given the premises.
An option contradicts the given information. This defines the logical relationship where a statement cannot be true given the premises.
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Which must be false if 'No cars are boats'?
Which must be false if 'No cars are boats'?
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Some cars are boats. This violates the negative universal by asserting overlap.
Some cars are boats. This violates the negative universal by asserting overlap.
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Identify the false statement: 'If A, then B.'
Identify the false statement: 'If A, then B.'
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A occurs and B does not occur. This creates a logical contradiction by affirming the antecedent while denying the consequent.
A occurs and B does not occur. This creates a logical contradiction by affirming the antecedent while denying the consequent.
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Which must be false if 'No reptiles are birds'?
Which must be false if 'No reptiles are birds'?
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Some reptiles are birds. This violates the negative universal by asserting taxonomic overlap.
Some reptiles are birds. This violates the negative universal by asserting taxonomic overlap.
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Identify the false statement: 'If X, then Y.'
Identify the false statement: 'If X, then Y.'
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X occurs and Y does not occur. This breaks the conditional logic by having X true but Y false.
X occurs and Y does not occur. This breaks the conditional logic by having X true but Y false.
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Which must be false if 'No rectangles are circles'?
Which must be false if 'No rectangles are circles'?
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Some rectangles are circles. This violates the negative universal by claiming geometric overlap.
Some rectangles are circles. This violates the negative universal by claiming geometric overlap.
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Which must be false if 'No reptiles are birds'?
Which must be false if 'No reptiles are birds'?
Tap to reveal answer
Some reptiles are birds. This violates the negative universal by asserting taxonomic overlap.
Some reptiles are birds. This violates the negative universal by asserting taxonomic overlap.
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Which option must be false if 'No dogs are cats'?
Which option must be false if 'No dogs are cats'?
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Some dogs are cats. This directly contradicts the negative universal statement about dogs and cats.
Some dogs are cats. This directly contradicts the negative universal statement about dogs and cats.
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Identify the false statement: 'If A, then B.'
Identify the false statement: 'If A, then B.'
Tap to reveal answer
A occurs and B does not occur. This creates a logical contradiction by affirming the antecedent while denying the consequent.
A occurs and B does not occur. This creates a logical contradiction by affirming the antecedent while denying the consequent.
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Which must be false if 'No cars are boats'?
Which must be false if 'No cars are boats'?
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Some cars are boats. This violates the negative universal by asserting overlap.
Some cars are boats. This violates the negative universal by asserting overlap.
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Which must be false if 'All students passed the exam'?
Which must be false if 'All students passed the exam'?
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Some students failed the exam. This directly opposes the universal success claim.
Some students failed the exam. This directly opposes the universal success claim.
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Which must be false if 'No spiders are insects'?
Which must be false if 'No spiders are insects'?
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Some spiders are insects. This violates the negative universal by claiming taxonomic overlap.
Some spiders are insects. This violates the negative universal by claiming taxonomic overlap.
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Which option must be false if 'No bears are birds'?
Which option must be false if 'No bears are birds'?
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Some bears are birds. This violates the negative universal by asserting impossible taxonomic overlap.
Some bears are birds. This violates the negative universal by asserting impossible taxonomic overlap.
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Identify the false statement: 'If T, then U.'
Identify the false statement: 'If T, then U.'
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T occurs and U does not occur. This breaks the conditional by having T occur while U doesn't occur.
T occurs and U does not occur. This breaks the conditional by having T occur while U doesn't occur.
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Which must be false if 'No whales are fish'?
Which must be false if 'No whales are fish'?
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Some whales are fish. This violates the negative universal by claiming taxonomic overlap.
Some whales are fish. This violates the negative universal by claiming taxonomic overlap.
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Identify the false statement: 'If K, then L.'
Identify the false statement: 'If K, then L.'
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K occurs and L does not occur. This violates the conditional by having K true but L false.
K occurs and L does not occur. This violates the conditional by having K true but L false.
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Which must be false if 'No sharks are mammals'?
Which must be false if 'No sharks are mammals'?
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Some sharks are mammals. This violates the negative universal by claiming taxonomic overlap.
Some sharks are mammals. This violates the negative universal by claiming taxonomic overlap.
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Identify the false statement: 'If M, then N.'
Identify the false statement: 'If M, then N.'
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M occurs and N does not occur. This breaks the conditional by having M occur without N occurring.
M occurs and N does not occur. This breaks the conditional by having M occur without N occurring.
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Which must be false if 'No trees are animals'?
Which must be false if 'No trees are animals'?
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Some trees are animals. This violates the negative universal by asserting impossible category overlap.
Some trees are animals. This violates the negative universal by asserting impossible category overlap.
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Which option must be false if 'No bananas are vegetables'?
Which option must be false if 'No bananas are vegetables'?
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Some bananas are vegetables. This contradicts the negative universal by claiming category overlap.
Some bananas are vegetables. This contradicts the negative universal by claiming category overlap.
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Identify the false statement: 'If P, then Q.'
Identify the false statement: 'If P, then Q.'
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P occurs and Q does not occur. This violates the conditional by having P true while Q is false.
P occurs and Q does not occur. This violates the conditional by having P true while Q is false.
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Identify the false statement: 'If W, then X.'
Identify the false statement: 'If W, then X.'
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W occurs and X does not occur. This breaks the conditional by having W occur without X occurring.
W occurs and X does not occur. This breaks the conditional by having W occur without X occurring.
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Which must be false if 'No rectangles are circles'?
Which must be false if 'No rectangles are circles'?
Tap to reveal answer
Some rectangles are circles. This violates the negative universal by claiming geometric overlap.
Some rectangles are circles. This violates the negative universal by claiming geometric overlap.
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Identify the false statement: 'If M, then N.'
Identify the false statement: 'If M, then N.'
Tap to reveal answer
M occurs and N does not occur. This breaks the conditional by having M occur without N occurring.
M occurs and N does not occur. This breaks the conditional by having M occur without N occurring.
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What does 'must be false' mean in logical reasoning?
What does 'must be false' mean in logical reasoning?
Tap to reveal answer
An option contradicts the given information. This defines the logical relationship where a statement cannot be true given the premises.
An option contradicts the given information. This defines the logical relationship where a statement cannot be true given the premises.
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