Logical Reasoning in the Supermarket: Adult Females' Use of Proportional Reasoning Strategy in an Everyday Context

Adult female shoppers in a supermarket were asked to determine which of two sizes of a common item sold in the store was the better to buy. Only 32 percent were able to use a proportional reasoning strategy to determine the correct choice when the size ration was a simple one (2:3). Performance declined even further (20 percent) when the ratio was more complex.