Mathematics Teaching in the Middle School · 2000 · 84 citations · 0 references
EducationEconomicsBehavioral EconomicsNumber SenseProportional ReasoningInformal Reasoning About ProportionProportion LearningProportional Reasoning AssessmentProportional Reasoning InstructionProportionality In Costs
Ellen, Jim, and Steve bought three helium-filled balloons and paid $2 for all three. They decided to go back to the store and buy enough balloons for everyone in the class.