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# Rational numbers

* A rational number is a number that can be expressed as a fraction `p/q` of two integers, a numerator `p` and a non-zero denominator `q`.
* Since `q` may be equal to 1, every integer is a rational number.
* The set of all rational numbers is denoted by ℚ (quotient).
* The decimal expansion of a rational number either:
  * terminates after a finite number of digits
  * infinitely repeats a particular finite sequence of digits
* Rationals may be build from the natural numbers by including a multiplicative inverse, `1/n`, for each nonzero integer `n`, along with the products formed by multiplying these inverses with integers.