Today the teaching of probability relies considerably on the use of software, particularly when it comes to simulation of diverse random experiments. This article, which refers to the theoretical framework of Kuzniak’s mathematical working spaces, studies an emblematic type of tasks frequently proposed to the French students aged 16-17 years. To accomplish these tasks, spreadsheets are used alternately as random event generator, calculator and logical tool. For this reason, the student was provided with many “technical” indications on the use of the software. Simultaneously, he must elaborate a model of the experiment, then simulate it by means of the software, and to do it, he must explore through various probabilistic and statistic paradigms, and hence through many working spaces, but no explicit indication helping him to identify the right paradigm is offered. Additionally, the task verbalization is often ambiguous, which turns difficult to determine the paradigms on which he is supposed to act.