3/4 is real & rational
-12/3 is real, rational, whole number & integer
0.345345345 is real and rational
-0.647349024 is irrational
Why?
3/4 is rational because it can be written as a fraction. Anything that's rational automatically is also considered a real number.
-12/3 is -4. -4 is an integer (a whole number) which automatically makes it real and rational.
0.345345345 is real because its a repeating decimal. If it wasn't repeating then it wouldn't be real and it wouldn't be rational.
-0.647349024 is just irrational cause its not a repeating (or terminating) decimal. :)