Saw this one on a professors door:

The evolution of mathematics education

during the last 30 years.

1960s

A peasant sells a bag of potatoes for $10. His costs amount to 4/5 of his
selling price. What is his profit?

1970s

A farmer sells a bag of potatoes for $10. His costs amount to 4/5 of his
selling price, i.e. $8. What is his profit?

1970s (New Math)

A farmer exchanges a set P of potatoes with a set M of money. The cardinality
of the set M is equal to $10 and each element of M is worth $1. Draw 10 big
dots representing the elements of M.

The set C of production costs is comprised of 2 big dots less than the set M.
Represent C as a subset of M and give the answer to the question: What is the
cardinality of the set of profits? (Draw everything in red).

1980s

A farmer sells a bag of potatoes for $10. His production costs are $8 and his
profit is $2. Underline the word potatoes and discuss with your classmates.

1990s

A kapitalist pigg undjustlee akires $2 on a sak of patatos. Analiz this tekst
and sertch for erors in speling, contens, grandmar and ponctuassion, and
than ekspress your vioos regardeng this metid of geting ritch.

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