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)

A logger sells a truckload of lumber for $100. His cost of production
is 4/5 of this price, or 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 a dollar. Make a square array of 100 dots to represent the elements of set M. The set C of the cost of production contains 20 fewer elements than set M. Represent set C as a subset of K and answer the following question:
What is the cardinality of set P of profits?

1980

A logger sells a truckload of lumber for $100. His cost of production is $80 and his profit is $20. Your assignment is to underline the number 20.

1990 (Outcomes-based destreamed integrated Math)

By cutting down beautiful forest trees, an environmentally ignorant logger makes a profit of $20. What do you think of this way of making a living? In your group, use role play to determine how the forest birds and squirrels feel.

Source: http://seanm.ca:70/stuff/math-problem.txt