I have to confess--I've never really enjoyed math. I always did okay in it, but it never came naturally to me, and it was the sort of thing that tended to go right back out of my brain as soon as the class or test was over. I am ALWAYS turning to Justin for even basic addition and multiplication. I just can't do it in my head.
I also never really bought the fact that I'd use things like algebra, calculus, and trig in real life. In fact, I never had until today...when I was trying to figure out what size my knitting needles were. Most of them are labeled, but these weren't.
So, I used a piece of yarn to measure the circumference, and then used the circumference to determine the diameter, and then converted that to milimeters, which gave me the approximate knitting needle size.
Who knew that algebra could be beneficial in knitting!?