Real numbers<span> can either be </span>rational<span> or irrational. ... A </span>rational number<span> is a </span>number<span>which can be written as a ratio of two whole </span>numbers<span> (</span>integers). For example 5 is arational number<span> since 5 can be written as ratio of 5 : 1 . 5 is also an </span>integer. 2.5 is arational number<span> since it is a ratio of 5 : 2 .
