Arithmetic Test

1960's arithmetic test: A logger cuts and sells a truckload of lumber for $100. His cost of production is four fifths of that amount. What is his profit? 1970's new-math test: A logger exchanges a set (L) of lumber for a set (M) of money. The cardinality of set M is 100. The set C of production costs contains 20 fewer points. What is the cardinality of set P of profits? 1980's "dumbed down" version: A logger cuts and sells a truckload of lumber for $100. His cost is $80, his profit is $20. Find and circle the number 20. 1990's version: An unenlightened logger cuts down a beautiful stand of 100 trees in order to make a $20 profit. Write an essay explaining how you feel about this as a way to make money. Topic for discussion: How did the forest birds and squirrels feel?