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Hint to this test: By "numbers" we mean real numbers here.

Which of the following statements is true?

0.81 is a rational number       2/3 is a rational number         __ √ 2  is a rational number           __ √ 7  is a rational number           __ √ 9  is a rational number           ___ √ 10  is a rational number         π is a rational number

out of points

The rational numbers are exactly those numbers

which are not integer       which are not irrational       which may be represented as fractions between two integers       which may be represented as fractions between two prime numbers       whose decimal representation terminates at some position       whose decimal representation becomes periodic at some position       which are not square roots of natural numbers

out of points

There are infinitely many

prime numbers       even prime numbers       integers < 5       natural numbers < 5       rational numbers between 0 and 1       real numbers between 0 and 10

out of points

The following operation may always be performed within the set of natural numbers:   multiplication       division (except by 0)       taking the square root       inverting (except 0)       taking the absolute value         out of points

The following operation may always be performed within the set of integer numbers:   multiplication       division (except by 0)       taking the square root       inverting (except 0)       taking the absolute value         out of points

The following operation may always be performed within the set of rational numbers:   multiplication       division (except by 0)       taking the square root       inverting (except 0)       taking the absolute value         out of points

The following operation may always be performed within the set of real numbers:   multiplication       division (except by 0)       taking the square root       inverting (except 0)       taking the absolute value         out of points

 

You have achieved    out of    possible points.

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