explain why the product is always less than one when you multiply a fraction by another fraction

Because when you do that ...-- you're starting with a piece that's less than ' 1 ', and-- you're calculating a piece of it that's less than the whole original piece.

so a proper fraction (one that is less than one like 1/2 and not 5/3) is always less than oneby definition, a fraction means a 'part of'  so if you multiply a fraction of a fraction it is like finding a part of a part and if the origonal part was less than one, then the result will be less than one like 1/2 of 2/4= (2/4=1/4+1/4) so 1/2 of 2/4=1/4 which is less than one