A logger sells a truckload of lumber

1960: “A logger sells a truckload of lumber for $100. His cost of production is 4/5 of this price. What is his profit?”

1970 (traditional math): “A logger sells a truckload of lumber for $100. His cost of production is 4/5 of this price; in other words, $80. What is his profit?”

1970 (new math): “A logger exchanges a set L of lumber for a set M of money. The cardinality of set M is 100, and each element is worth $1. Make one hundred dots representing the elements of the set M. The set C of the costs of production contains 20 fewer points than set M. Represent the set C as a subset of M, and answer the following question: What is the cardinality of the set P of profits?”

1980: “A logger sells a truckload of wood for $100. His cost of production is $80, and his profit is $20. Your assignment: underline the number 20.”

1990 (Outcome Based Education): “By cutting down beautiful forest trees, a logger makes $20. What do you think of this way of making a living? (Topic for class participation: How did the forest birds and squirrels feel?)”