Answer:
The given number is a rational number.
Step-by-step explanation:
We know that a rational number is a number than can be expressed in the terms of p/q were p is an integer and q are rational numbers.
Now, we know that if a decimal expansion is non-terminating ( that is it does not end) and is repeating ( i.e. the terms after decimal repeats ) than it can also be expressed in terms of p/q.
Hence, the given number :
-0.6666666....
( Clearly it is a rational number as the expression is a decimal number which is non-terminating and is repeating and can be expressed in terms of p/q as -2/3 )
