Solve this equation for me

[MrRubix]

Re: Solve this equation for me

Well it depends on what you want to do but yeah

[GG_Guru]

Re: Solve this equation for me

What was it that you wanted to do Marcus?

Umm, something about business right? I have a very foggy memory I can't remember squat sorry.

[leonid]

Re: Solve this equation for me

What did I do wrong lol
I just did E(profit) = $4 * .125 + ($-1) * .875 = $-.375

Wait, were you asking for expected profit or loss from trying to winning twice?

In that case, $-6... If this is wrong again, then I'll give up lol

[GG_Guru]

Re: Solve this equation for me

Dude get the **** out with that math problem lol.

Didn't you read my earlier post?

My unnecessary, over excessive post?

[MrRubix]

Re: Solve this equation for me

leonid: Hint: Since you know you'll win twice upon completion, let X = number of $1 tickets bought. Your profit is 10 - X since winning twice = 5*2 = 10 dollars -- you want to find E(Profit)

Yes you wanna find the E(Profit) of just winning twice in general (hence the question's phrasing)


EDIT: Yes -6 is right :P



Guru: Yes, I graduated from a business school, but I'm really a compsci dude at heart.

[leonid]

Re: Solve this equation for me

You win $4 for each winning tickets, because you get $5 but you already paid $1 for one..


edit: thanks for confusing me with problems that lack clarification >:0
edit2: I happen to know how to solve those problems as I'm taking intro to stats this semester lol

[GG_Guru]

Re: Solve this equation for me

Fellas, fellas..

The answer is obviously:

[MrRubix]

Re: Solve this equation for me

leonid: E(10-X) = 10 - E(X) = 10 - (2/.125) = -6

[leonid]

Re: Solve this equation for me

I did that while writing that post...

I don't know how to solve that problem you told us none of us will be able to figure out.. I tried the first part but I found myself having to solve a quintic polynomial inequality >_>

[GG_Guru]

Re: Solve this equation for me

HEY!

You guys wanna solve math problems?

Find the full value of pi.

Good luck I'll see you in forever minutes.

[leonid]

Re: Solve this equation for me

[GG_Guru]

Re: Solve this equation for me

+......?

[RB_Killer]

Re: Solve this equation for me

OMFG, are you srsly kidding me???? Some retarded 8th Grader can do this, I swear to god. (referring to GG-Guru's first post)

[MrRubix]

Re: Solve this equation for me

leonid: Alright, harder problem for you (I've always loved this problem -- was given to me in an interview).


You have a building with 100 floors, and you've got two glass spheres. These spheres are identical and breakable when dropped from a certain floor. For instance, if these spheres begin to break when dropped from floor X, that means they will also break any any floor above X and not break at any floor below X.

Once a sphere breaks, you lose that sphere. Develop an algorithm where you can guarantee me a maximum number of drops needed to find which floor is where the spheres' breakpoints are (it's possible that they'll survive even from floor 100).

Example: Worst algorithm: Start at floor 1, drop. If it doesn't break, drop from floor 2, etc... if the breakable floor was X=100, then that means you needed 100 drops.

[GG_Guru]

Re: Solve this equation for me

God damn it Rubix...
>.<