Boring info on my life, with interspersed tidbits on computers, math, and other such topics.

Dec 11, 2006

POTD 65

POTD

Haha, go Hendrix!

Yeah whatever... UMTYMP test on Wednesday that I need to study for. >.< But I got a 96/100 on my physics test, so I'm pretty pleased with myself. Party this weekend, with funny (so bad it's funny) movie afterwards! Everyone should come.

Dec 8, 2006

POTD 64

POTD

Woo, another philosophy paper, English paper, physics test, and UMTYMP test. If I had a debate tournament this week I probably would have died.

Blargh. A Realm Divided is actually going somewhere, albeit slowly due to my math and stuff.

I got five new CDs today. :D So much listening to do.

Dec 7, 2006

POTD 63

POTD

Hmm, I always thought WWII airplanes looked really cool for some reason.

Dec 6, 2006

POTD 62 + Other Stuff

POTD

Pretty nice geezer. The texturing is nice, and that's some pretty high poly modeling.

Yay, another double UMTYMP assignment. I just love 'em.

Whatever, anyways for those of you doing Mathcounts I'm going to try and give training tips via my blog. If any of you aren't doing Mathcounts and don't want to better yourselves, then promptly ignore everything below.

Probability:

Most of you probably can do pretty basic probability problems such as finding the probability of a coin flipping heads twice in a row. How do you do it? You simply multiply the probability of both events happening, so in the case of the coin flip we have (1/2) * (1/2) = 1/4. So far nothing too difficult, so lets up the complexity.

What is the probability that a ball starting in the blue oval will end up in the red oval, assuming the ball travels down and has an equal probability of moving down each chute?

Obviously the probability the ball ends up in the first oval beneath the blue oval is 1. Now the probability that the ball ends up in the oval above the red oval is 2/3, since the ball has three paths and two of them takes it to the oval we want it at. Now the ball has two choices: to go right and end up in the red oval, or go left. So our total probability is 1*(2/3)*(1/2) = 1/3.

As you might have guessed multiplying probabilities in not the only way find a probability.

Lets consider this problem: Albatross, Bobert, Caddlebot, Deberg, and Eustien are in the senate. Three of them will be randomly chosen to head a committee to study the causes of bureaucratic inefficiency. What is the probability that Albatross will be in the committee? Now the old way of calculating probabilities won't work too well. Another way is to take the total number of possibilities that work and divide by the number of possibilities total. So in the case of this problem we would count the number of committees that include Albatross and then divide by the total number of committees.

Let us calculate the number of committees total. Here we use an operation called "choose". Choose is denoted (b,a) except that b would be on top of a; it's like a vertical parenthesis. (b,a) tells use the number of committees of size a that we can choose from a group of b people. The formula is (b,a) = b!/(a!*(b-a)!), where ! denotes factorial. I think you know this, but just to recap 5! = 5*4*3*2*1 and 0! = 1.

So the total number of committees to form is (5,3) = 5!/(3!*2!) = (5*4*3*2*1)/(3*2*1*2*1) = 10. Now we calculate the number of committees that include Albatross, at this point we could just count them, but that isn't that efficient. A better way is to assume that we have already chosen Albatross, and then we are picking the remaining two members of the committee. So the number of committees that include Albatross is (4,2), since we are choosing two people out of a group of four remaining people. This number is 6. So the probability is 6/10=3/5.

I'll leave you with a challenge problem. A bug is walking on a triangle. A "move" consists of the bug moving from the vertex he is standing on to one of the other two vertexes. After 10 moves what is the probability that the bug will return to the vertex it started on?
Hint: Consider the moves he makes as a series of letters, with R denoting a right turn, and L denoting a left turn.
Hint 2: Think about the relation between the number of R and L turns it makes to where it ends up, in particular think of the number of right moves it must make to return to the original point.

I'll post the solution after a while...

This is definitely the longest post I have ever made. Woohoo!

Dec 5, 2006

POTD 61

POTD

Ooh white plastic.

Not too much going on.

Dec 4, 2006

POTD 60

POTD

Cool stuff, I like the castle in the background. The crows add a nice amount of atmosphere to the already moody looking palette.

Debate went okay. The tournament tried something really different, they group varsity and novice together, so I kept hitting people way better than me. Hitting varsity people means I didn't break, but apparently I'm somehow good at speaking now, so I won seventh best speaker, which is cool considering there were at least 150ish people there.

Argh, I've got to take a test for physics, and calculus soon. Life is so cruel sometimes, and by sometimes I mean all the time.

Haha, the second time you read Eragon (or as many times as it takes to get over Paolini being young and homeschooled) you notice that the book is steaming peice of crud. I'm very seriously thinking abou seeing Star Wars episode IV digitally remastered and placed in a medieval setting when it comes out on the 15th, just so that I piss off fan boys. And btw, the Eragon game I can guarantee will be a piece of crud.

Dec 1, 2006

POTD 59

POTD

So cool looking. O_O Seriously though, nice metal, nice lighting.

So I finished NaNoWriMo; though I don't really count myself as finishing until Esillisar stops having dreams of the ways with which he would disprove the theories of Madisonian democracy.

I also beat NetHack again about a week ago. Go me.

Going to another debate tournament in a few hours. *sigh* My cases still suck.