Proceedings of the Annual Meeting of the Cognitive Science Society

People encounter improper fractions in real life contexts on a regular basis. One such example is with bundling at thegrocery store (2/$4 or two for $4). The present study seeks to understand how people process these bundle prices comparedto improper fractions. Participants completed a magnitude comparison task with different bundling formats (2/$4 vs. $4/2)and their fractional equivalents. We found a reliable difference between the bundle format (2/$4) seen in grocery storesand the most visually similar fraction (2/4). This difference shows that participants are not using a heuristic (larger fractionmeans cheaper per item) when comparing these bundle deals and instead do need to process them like improper fractions.Overall, we found that participants were better at comparing fractional magnitudes in a math context than in a financialcontext and that this effect of context also depended on format (2/4 vs. 4/2).