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Valid and Invalid

For each of the following deductive arguments, determine whether it is valid or invalid.

1 / 15

Nine is greater than four, and four is greater than six. Thus nine is greater than four.

2 / 15

If Mahatma Gandhi was a woman, then Mahatma Gandhi was a female. But Mahatma Gandhi was not a woman. Therefore Mahatma Gandhi was not a female.

3 / 15

The word ‘wet’ has three letters in it. Thus the word ‘wet’ has an odd number of letters in it.

4 / 15

Either the former U.S. president George W. Bush was not a professional baseball player or he was not a famous rock singer. But he was a famous rock singer. Thus George W. Bush was not a professional baseball player.

5 / 15

Some dogs are mammals. Some dogs are poodles. Thus some mammals are poodles.

6 / 15

If Bertrand Russell wrote a book on advanced logic, then he was a logician. Bertrand Russell did indeed write a book on advanced logic. And either he was not a logician or he was a ballet star. Thus Bertrand Russell was a ballet star.

7 / 15

This geometric figure is a square. Therefore, this geometric figure has exactly three sides.

8 / 15

Snow-covered landscapes are chilly. Hence, snow-covered landscapes are cold.

9 / 15

All cats are tigers. No tigers are fish. Thus no cats are fish.

10 / 15

René Descartes is now the U.S. President. Thus René Descartes is now the U.S. President.

11 / 15

Some dogs are German shepherds. Thus some dogs are not German shepherds.

12 / 15

If Malcolm X was a National Hockey League star, then Malcolm X was a professional athlete. Malcolm X was not a professional athlete. Thus Malcolm X was not a National Hockey League star.

13 / 15

Bob is a gzworg. Thus Bob is a gzworg.

14 / 15

Elephants fly. Elephants are animals. Thus some animals fly.

15 / 15

Five is greater than two. Two is greater than ten. Thus five is greater than ten.

Your score is

The average score is 63%