This paper is a complement of the research report "The Euclidean division implemented with a floating-point division and a floor", RR-5604, INRIA, June 2005. Here we study conditions under which the floor of an exact product (or the Euclidean division, when the divisor can be known in advance) can be implemented using a floating-point multiplication followed by a floor function. The example of the Euclidean division by 3 is given.