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Hello and welcome to Caratalk from National Public Radio with us, Click and Clack the Tappert Brothers, and we're broadcasting this week from the Center for Applied Sociomathematics here

at Caratalk Plaza.

Now, this was sent to us by Creighton-Trayan from, I guess, University of Kentucky.

And I don't know if he's the author, but... No one knows who the authors are of anything anymore. You just pass it on, put it on your mailing list, and it's gone. But here it is. Go ahead. Here it is. Go ahead. It's about the teaching of mathematics. Yes. And how it has changed over the past few decades. Yes. And it gives examples of questions that people had to answer.

Teaching math. Yes. And how it has changed over the past few decades. Yes. And it gives examples of questions that people had to answer.

Teaching math in the 50s. Here's a question. A logger sells a truckload of lumber for $100.

His cost of production is four-fifths of the price. What is his profit?

One-fifth. You probably did. You probably did problems like that.

Teaching math in the 60s.

A logger sells a truckload of lumber for $100.

His cost of production is four-fifths of the price or $80.

What is his profit?

Teaching math in the 70s.

A logger exchanges a set L of Lumba for a set M of money.

The cardinality of set M is 100.

Each element is worth $1.

Make 100 dots representing the elements of the set M.

...