## 27 August 2005

### Tropic of calculus

In the middle 1960s, Tom Lehrer put New Math in its place. Unfortunately, it didn't stay there. Jeff Quinton traces the evolution of a standard math problem, starting in 1965; after thirty years it was almost unrecognizable.

1965  A logger sells a load of wood for \$100. His cost of production is \$80. What is his profit?

1970  A logger sells a load of wood for \$100. His cost of production is \$80. What is his profit?

1975  A logger sells a load of wood for 100 units (make a set of 100 dots to represent this income.) His production is 80 units. The units of sell and cost interchangeable. Draw a subset with 80 dots respresenting cost. The difference between the set and subset is the profit.

1985  A logger sells a load of wood for \$100. His cost of production is \$80. His profit is \$20. Underline \$20.

1995  A logger makes his living cutting down beautiful trees. Discuss how the little birdies, animals and trees feel. Points given for discussion participation.

As Jeff notes, it's time for a 2005 version. This one came to me after a minute or so:

2005  A logger under contract to the Department of Defense sells a load of wood for \$100,000. His cost of production is \$600 for labor and equipment, \$800 for taxes, and \$7100 for environmental permits and certificates. How much profit will he have after Halliburton takes its cut?

Feel free to improve on this in Comments.

Posted at 6:38 PM to Dyssynergy

(On the flip side of the 1995 feel-good question, and I daresay only slightly tongue-in-cheek):