1958 to 2008: 50 Years of Math

Teaching Math In 1958
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 1968
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 1978
A logger sells a truckload of lumber for $100.
His cost of production is $80.
Did he make a profit?

Teaching Math In 1988
A logger sells a truckload of lumber for $100.
His cost of production is $80 & his profit is $20.
Your assignment: Underline the number 20.

Teaching Math In 1998
A logger cuts down a beautiful forest because heis selfish & inconsiderate & cares nothing for the habitat of animals orthe preservation of our wood-lands. 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 thequestion: How did the birds & squirrels feel as thelogger cut down their homes? (There are no wronganswers, & if you feel like crying, it's okay.)

Teaching Math In 2009
Un hachero vende una carretada de madera para $100.
El costo de las producciones es $80.
Cuanto dinero gana?