Cussedness

Innumerate Journalists

Point 4 in this rather daft article made me swear out loud, specifically this sentence:

Two divided by three makes 0.666 recurring (allegedly - actually it makes 0.6666666667).

What on earth are they teaching in hack school nowadays?

A quick visit to Wikipedia’s article on recurring decimals would have cleared this one up for our innumerate scribbler. Here’s their example with 2/3 instead of 1/3:

x = 0.666666...
10x = 6.666666... (multiplying each side of the above line by 10)
9x = 6 (subtracting the 1st line from the 2nd)
x = 6/9 = 2/3 (simplifying)

If you put 0.6666666667 in there, it doesn’t work anymore:

x = 0.6666666667
10x = 6.666666667
9x = 6.0000000003 (Oh dear)

Perhaps it’s a good thing that whoever wrote that piece didn’t visit that Wikipedia article, though. After wading through the sources for all the other bits of breathless numerological nonsense on that page, seeing the mathematical proofs for 1 = 0.999999… would probably have induced a nervous breakdown.

x = 0.99999...
10x = 9.9999...
10x − x = 9.9999... − 0.99999...
9x = 9
x = 1

3 comments • 2007-02-23 11:27 • Categories: Geek Stuff, Rage, Science & Maths • Tags: 0.9 Recurring, Idiot, Maths, Media