Changes in math

Last week I purchased a burger and fries at McDonalds for $3.58. The counter girl took my $4.00 and I pulled 8 cents from my pocket and gave it to her. She stood there,  holding the nickel and 3 pennies. While looking at the screen on her register, I sensed her discomfort and  tried to tell her to just give me two quarters, but she hailed the manager for help. While he tried to explain the transaction to her, she stood there and cried. Why do I tell you this? Because of the evolution in teaching math since the 1950s:

Teaching Math In the fifties:  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 the sixties:   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 the seventies:   A logger sells a truckload of lumber for $100. His cost of production is $80. Did he make a profit?

Teaching Math In the eighties:   A logger sells a truckload of lumber for $100. His cost of production is $80 and his profit is $20 Your  assignment: Underline the number 20.

 Teaching Math In the nineties:   A logger cuts down a beautiful forest because he is selfish and inconsiderate and cares nothing for the habitat of animals or the preservation of our woodlands. He does this so he can make a profit of $20. What do you think of this way of making a living? Topic for class participation after answering the question: How did the birds and squirrels feel as the logger cut down their homes? (There are no wrong  answers.)

Teaching Math In 2005:    Un ranchero vende una carretera de madera para $100. El cuesto de la produccion era $80. Cuantos tortillas se puede comprar?

Thanks Tommy Salami