According to Wikipedia(https://en.wikipedia.org/wiki/Pi), pi is defined as being the ratio of a circle's circumference to its diameter but also it is mentioned as an irrational number.
Also from Wikipedia (and high-school math), https://en.wikipedia.org/wiki/Irrational_number, an irrational number cannot be expressed as a ratio.
Therefore, how can pi be irrational and also a ratio? Don't they contrast? OR is the definition if pi wrong? If its a ratio shouldn't it be rational?