Daily living computational skills: the correct answer is not always the exact one

Exact computation is the most popular and latest acquired calculation skill, while approximation (e.g., 28+17 < or > 50?) and magnitude estimation (e.g., How long is a high-speed train?) are based on early developed mechanisms. Yet, despite their ecological relevance, these skills remain overlooked in the education and clinical contexts. Here, we explored individual differences in exact (e.g., 34+8?) and approximate (e.g., 250+531≈760 or 870) computation, ecological estimation (e.g., ‘How much does a bicycle weigh?’), and non-symbolic comparison. Specific Learning Disabilities (SLD, e.g., Dyscalculia) and educational background (STEM, Humanities, etc.) were also considered as sources of variability. Results show high internal variability, with estimation being particularly challenging. STEM and SLD participants exhibit extreme and opposite performances. Exact and non-exact tasks correlate, suggesting that although estimation and approximation are not formally acquired, they are grounded on formal calculation. The latter is a long-term trained ability across schooling. Still, everyday life requires much more: shifting the attention to everyday life computation is critical to redefine the focus of attention in a clinical setting.