A little math help

[drawn_inward]

I need a little math help. I suck at permutations, and such.

Here's what I am trying to figure out.

I have 5 mutable positions.

First position can be either: a/b
Second: c/d
Third: e/f
Fourth: g/h
Fifth: i/j/k

I think the number of possibilities should be 48, but I don't know how to calculate this.

Thanks!

BTW, this isn't for class - it's for work.

 

[fade]

You're right. There are 48.
the first four are just a binary number
2^4 = 16 (think of each as an on/off state). The last one gives you three additional branches. 3 * 2^4 = 48.

Or even simpler 2*2*2*2*3 = 48.

The formula is just (number of states)^(number of instances of those states)

 

[Bubble181]

2*2*2*2*3, so 48.

Damn you Dr Fade McNinja!

 

[drawn_inward]

Thanks guys. That's how I calculated it, but I haven't tried math like this in quite some time. It just seemed too easy. Thanks!

 

[fade]

If you're looking for information on counting problems (such as if this comes up at work again), look up "combinatorics".

 

[PatrThom]

This also has applications when playing the lottery.
Mostly the results should just tell you why you shouldn't play the lottery.

--Patrick

 

[drawn_inward]

This also has applications when playing the lottery.
Mostly the results should just tell you why you shouldn't play the lottery.

--Patrick

Definitely. The lottery preys on the dim-witted and the desperate.

 

[Koko]

On a separate note
What's everyone's highest course of mathematics taken academically?
Started calculus this semester

 

[Jake]

Had to take 5 Calc courses and a linear/matrix algebra course that hurt my brain.

Also "Principles of nuclear magnetic resonance" in grad school was a mindfuck (not the good kind, the bend-over-and-take-it-all kind).

 

[drawn_inward]

Calculus III, Physics II, and Discrete Math

Discrete Math sucked, I liked Physics (well, mechanics), and Calculus wasn't all that interesting.

 

[Adam]

Managerial Accounting. *sob*

 

[PatrThom]

Never advanced beyond secondary school calculus.
Still find it all quite fascinating, though.

--Patrick

 

[fade]

I'm a (geo)physicist, so I have a lot of math under my belt. Don't know (ironically) how to quantify it, since a lot of it came from physics study and research. Formally, up through probably junior or senior year of a math major, when things get all number-theoryish, which means "useless to a physicist". Though I still like reading about it. Tons of computer science math and probability and statistics. Most of my research is in diff eq. solutions and probability theory.