Clashes of slashes or the division of dividers

This video is in English.
Length: 22:16
Source: NLPW - Nederlandse Perl Workshop 2014 on the 2014-04-25.
Speaker: Theo van Hoesel speaker
abstract

Have you ever had 0.125 pizza? Maybe 1/8th of a pizza? Theo van Hoesel, who is also a Math teacher, explains the difference between the two.

He is also showing what 9/4/1/2 is, and what it is not.

Then he introduces Number::Fraction and how he extended it.