Connecting representations for understanding probabilities requires unfolding concepts in meaning-related language

It is well known that multiple representations can enhance students' conceptual understanding, but only if (potentially superficial) translation activities are deepened by making the connections explicit. But what exactly does that mean? In our qualitative analysis of a design experiment with two twelfth graders from vocational school on conditional probabilities, we show that explicating connections between multiple representations requires processes of unfolding a highly compacted concept into its concept elements (in our case, part, whole and part-whole-relationship) and articulating them in a decontextualized meaning-related language. By this, we intend to contribute to the research identifying conditions of success for working with multiple representations also for high school students.