99.78 is a irrational (sorry had to double check this one) number.
Square root of 3 is not rational it is irrational.
-11/6 is a rational number
3n is a rational number.
square root of 16 is a rational number.
Definition of irrational numbers: But some numbers cannot be written as a ratio of two integers...they are called Irrational Numbers.
Definition of rational number: A Rational Number can be made by dividing two integers. An integer is a number with no fractional part