The number 21 is a rational number if 21 can be expressed as a ratio, as in RATIOnal.
A quotient is the result you get when you divide one number by another number. For 21 to be a rational number, the quotient of two integers must equal 21.
In other words, for 21 to be a rational number, 21 must be able to be expressed as a ratio where both the numerator and the denominator are integers (whole numbers).
The number 21 can be expressed as 21/1 where 21 is the numerator and 1 is the denominator.
Thus, the answer to the question "Is 21 a rational number?" is YES.
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Is 22 a Rational Number?
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