Yes this is the exact definition of what it means to be a rational number. A rational number is one that is a fraction of two whole numbers (or integers). The denominator, or the number in the bottom of the fraction, cannot be 0.
Some examples: 7 = 7/1 2/3 8/10 0.5 (since this equals 1/2) the square root of 64 (since it equals 8 = 8/1) any repeating decimal any terminating decimal
Non-examples are things like... sqrt(7) pi log(3) any decimal where there isn't a clear pattern that repeats