Teaching Math In 1950s:
A logger sells a truckload of lumber for $100.His cost of production is 4/5 of the price. What is his profit?
Teaching Math In 1960s:
A logger sells a truckload of lumber for $100. His cost of production is 4/5 of the price, or $80. What is his profit?
Teaching Math In 1970s:
A logger sells [...]