Answer:
Rational
Step-by-step explanation:
A rational number can be written as a fraction of the form.
[tex] \frac{a}{b} \: where \: b \ne0[/tex]
and a and b are integers.
[tex]9.99 = \frac{999}{100} [/tex]
Hence in this case a=999 and b=100.
Since both are integers with b being a non-zero integer, we conclude that 9.99 is a rational number.