Consumers make poor purchase decisions when they need to work with ratios to assess a product’s value, says a new study published in the May 2017 of the Journal of Marketing Behavior, from the University of Miami School of Business Administration. In situations where consumers must average ratio information, such as comparing the fuel efficiency of two cars using the ratio miles per gallon, they often flub the numbers by incorrectly assuming the mathematic equation to find miles per gallon would be to average the sum of the mileage of both cars and then divide by two, instead of using a more complex equation needed to accurately compare ratios. This incorrect way of crunching the numbers leads to only 25-30 percent of shoppers getting the correct answer.