Excluding math-related careers, is there any point in real adult life when you're actually going to need to know how to factor a quadratic equation or what the sine of 60 is? I'm feeling a bit fed up.

How to launch a space shuttle to dock with the space station requires mega-math, unless they are just being lucky

Challenger..... Columbia......Not quite so lucky.

It is also important if you want to play piano: How could you play a Bach's waltz without maths?

I dont know if Bach wrote any waltzes, but if he did it would be 1,2,3 1,2,3.

I had a teacher in junior high who had a chart on the wall with math used in different careers. If you're in science, business, etc. you might. Otherwise, most of them were math up to 8th grade.

Most girls don't take four years of math in high school, and with that decision they end up disqualifying themselves from 90% of possible careers.

You can ask this question about around 90% of the stuff you learned at high-school.

As far as I'm aware, he didn't. That means you count i, 2i, 3i i, 2i, 3i.