Do the math, or we'll keep falling for lies

More than 25 years ago, just as Proposition 13 was taking effect, I remember hearing then-Supervisor Rod Diridon Sr. boast how Santa Clara County had regularly decreased its tax rate, the amount it charged per $100 of property value. Sir Rod, selfless tax-cutter. What he didn't explain was that soaring property values -- many more $100 chunks -- had resulted in larger tax bills, not smaller. Multiplication as mystery.
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``I think one-half of the adults in the U.S. cannot either read a graph or draw a graph,'' says Willow Glen High School math teacher Chuck Acampora. ``They're turned off because they don't understand the fundamental operations of math.''

I think he is being a little conservative, I think it is much worse then that. I was in a Honors class my first year in college and during the biology section the teacher put up a table that compared the amount of material in various cells of the body. Something like:
Skin: 6.1325
Liver: 6.431
Stomach: 6.362
Egg: 3.890
And most of the class was baffled by the Egg, some had a hard time with the fact that it had half the material of the other cells and other by the fact that it wasn't exactly half, they were stressing over the fact that in nanograms the difference was so large. The most significant digit was a concept that he had to teach most of the class.

Without a good understanding of what numbers can and cannot tell you, you are easy fodder to people who are willing to use numbers to confuse you. You cannot make good decisions in a confused state.

A good way to stay poor is to not have a good idea of what happens to your money over time.