New Math, Old Math

[Mr. Sandman]

Last week I purchased an item 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.

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Why do I tell you this?

Because of the evolution in teaching math since the
1950s:

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?


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?


Teaching Math In 1970

A logger sells a truckload of lumber for $100. His
cost of production is $80. Did he make a profit?


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.


Teaching Math In 1990

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?