Last week I purchased a burger at Burger King for $1.58. The counter girl took my $2 and I was digging for my change when 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.<br /><br />I sensed her discomfort and tried to tell her to just give me two quarters, but she hailed the manager for help.<br /><br />While he tried to explain the transaction to her, she stood there and cried.<br /><br />Why do I tell you this?<br /><br />Please read more about the "history of teaching math":<br /><br />Teaching Math In 1950: A logger sells a truckload of lumber for $100. His cost of production is 4/5 of the price. What is his profit?<br /><br />Teaching Math In 1960: 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?<br /><br />Teaching Math In 1970: A logger sells a truckload of lumber for $100. His cost of production is $80. Did he make a profit?<br /><br />Teaching Math In 1980: 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.<br /><br />Teaching Math In 1990: By cutting down beautiful forest trees, the logger makes $20. What do you think of this way of making a living? Topic for class participation after answering the question: How did the forest birds and squirrels feel as the logger cut down the trees. (There are no wrong answers.)<br /><br />Teaching Math In 2005: El hachero vende un camion carga por $100. La cuesta de production es.............