It is interesting how the numbers we use in a math class are different from the numbers we encounter in real life. Over the summer, we were working with calculating the sales tax on a jacket that cost $60. In real life, nothing costs $60. The calculation for sales taxes is identical for something that is $59.99 or $60. I wonder if we used more realistic numbers, if students would be terrified by the slightly more complex calculations or it would help them feel more empowered in the real world.
|XKCD Original (I cropped to 'keep it rated G')|
Now, just for a bit of math before I go. What does 21/29 actually look like? Well, I started doing the long division to figure out what it was as a repeating decimal. After I got the 11th digit after the decimal point, without seeing a pattern, I stopped. I looked on my calculator (which only goes to 9 digits after the decimal point) to double-check my work. I was right, I still had to wait on the pattern. I used Wolfram to get a solution...
It goes for 28 digits before it starts to repeat! It got me thinking: I wonder what two-digit denominator would lead to the longest period/repeating part of a decimal. I would ask one of my professors, but I am afraid he would put the question on our next test. Back to math homework. Good night inter-web.