Inference, or decision making, is seen in curriculum documents as the final step in a statistical investigation. For a formal statistical enquiry this may be associated with sophisticated tests involving probability distributions. For young students without the mathematical background to perform such tests, it is still possible to draw informal inferences based on data of various sorts, for example by comparing two graphical representations. In doing so it is important to be able to state the assumptions that are the foundation for the decision made. This article considers a straightforward context where students are asked to make predictions. These predictions are informal inferences that can be based on aspects of the scenario, the students' appreciation of the context, and their cognisance of the data presented. (Contains 2 figures and 1 table.)