Which of the following is a counterexample of, "all rational numbers are integers"? is not an integer. 3 is an integer. -1 is a rational number. π is a rational number.

It is (almost certainly) the first choice, however, you omitted the actual example there. See below.

Step-by-step explanation:

A counter-example to "All rational numbers are integers" is easy to find - it is any fraction that is reduced to simplest form and its denominator (bottom part) is not 1. Examples: 2/3, 7/5, 11/13 are all not integers but rational numbers and therefore are counter-examples to the statement. The statement is thus disproven. Please check your question - there is a value with the first choice that is likely one such fraction.

The remaining 3 choices to your answer are all not applicable.

1/2 is not an integer

Step-by-step explanation:

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