Re: [Phys-l] innumeracy

[Rick Tarara <rtarara@saintmarys.edu>]

----- Original Message ----- 
From: "Robert Cohen" <Robert.Cohen@po-box.esu.edu>

> I'd be more concerned with the ratios than the actual numbers (although
> 800,000 for the US population seems a tad bit off the mark, even for
> me).  In particular, ten answers had ratios of ten or less.  Do they
> really think the US population is that large compared to the world
> population??  Not recognizing the ratio seems to me a bigger problem.
Ah--but there is the (IMO) number one math deficiency we see--the lack of 
understanding of ratios and the lack of ability then to do anything useful 
that involves ratios.  Even my Calc level class does miserably if I 
challenge them with algebraic ratios.  [Example--setup that a car can make a 
given radius turn at a given speed.  Now ask at what speed can they do half 
the radius, at what speed can they turn in the road becomes wet and the 
coefficient of friction is functionally halved, at what minimum radius can 
they turn at twice the speed, etc.]

More math  problems--5/26 people in my class today could not tell me 
correctly how many people the U.S. (currently at 300 million) would have 140 
years from now if the growth rate remained constant at a doubling time of 70 
years .  To be fair ;-) they weren't allowed to use calculators and the 
wrong answers (900 million or 1.8 billion) are sort of understandable (I 
have to start thinking--or not thinking--like them.)  ;-(

Rick