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Lumber-Yard Rounding?

Applications of math in the real world are good... but hopefully not sloppy.

My current beef: Why do they call lumber "two-by-fours" when it actually is "one-and-one-half-by-three-and-one-half"?

There is a big difference between the two. The first has a cross-sectional area of "eight," while the other leads to the more complicated "five-and-one-fourth."

Is this a purposeful attempt to deceive? Or, is it akin to the reverse effect of buying something at a price of $5.98, where we focus on the 5.

And, when trying to determine the history of this false business practice, I learned that our "two-by-four" is called a "four-by-two" in the UK, Australia, New Zealand. Big deal---misleading communications are commutative!

The culprit behind this false labeling is the Committee on Grade Simplification and Standardization. At a meeting in Scottsdale (AZ) in 1961, they formally adopted the American Lumber Standard set in 1924. Their reasoning assumes that lumber has one set of dimensions when green (not dried) and rough (unfinished), and that these dimensions shrink when the lumber is finished.

Sound like McDonalds game of selling something called "quarterpounder."