require 'rational'
require 'mathn'
rat = Rational(25/100) # => 1/4 -- lowest terms
rat % Rational(1/2) # => 1/4 -- modulo or remainder
rat**2 # => 1/16 -- exponent or power
rat == 1/8 # => false -- equality
rat == 1/4 # => true
rat <=> 1/4 # => 0
rat <=> 1/8 # => 1
rat <=> 1/2 # => -1