How many Yahoo screen names do I need to win 5 million dollars?

Half an hour with no solutions? I'm flabbergasted.

= ^ )

We already have the 64 teams arranged in their starting positions of the bracket. So our first decisions come with the first round of games, of which there are 32. Each game has two decisions we need to make. Similarly for the second round, there are 16 games, each game has 2 choices (we're certainly not going to choose one of the teams we've decided earlier will lose). Continuing, we end up with a total of

1+2+4+8+16+32 = 63

games, each with two choices for us to make, so

2^(63)

different brackets we could fill out. Dividing this by 5 will give you the number of screen names you need to guarantee the 5mil. My calculator, surprisingly, can do this out, and it would appear we need approximately 1.845*10^(18), or 1.845 quintillion screen names.

Let's keep going with this. I estimate it should take you, say, 30 seconds to create each screen name (without computer aid, and without messing up any of the forms). Then perhaps another 2 minutes to fill in a bracket (I have no idea how yahoo wants those entered...).

So every 5 brackets takes you about 10.5 minutes. Then we need

1.845 * 10^(18) * 10.5 / 60 = 3.228 * 10^(17)

or 322.8 quadrillion hours...we have about 18.5 hours at the time of posting this before tip-off. We seem to be a bit short of time.

Perhaps more later...how many people would it take helping, what kind of probabilities we have, etc...

EDIT: I'd be happy to join in the efforts, for my share of the profit. Perhaps others would do the same. Let's see how many people we would need in order to get it done in the 16 hours we have left (at the time of this edit).

We've already decided a total of about 322.8 quadrillion hours need to be put in. Dividing this by the number of helpers will give us our total number of working hours, which needs to be at most 16. Thus, we need

322.8quad / 16 = 2.018*10^(16)

or 20.18 quadrillion people. There are what, 6.6 billion people on the planet right now? So we're a factor of 3 million shy of our goal, and we would each earn well under a penny if we divided up the 5mil evenly. Perhaps we should have started planning earlier?

Let's see...the first games tend to have pretty good odds in favor of one team or the other, so let's just go with the odds on those. Then we have only 31 games to choose our favorites, for 2^31 choices. Then we need only have 429,496,730 yahoo accounts, for about 75,161,928 hours of work. Dividing again by 16 hours remaining, and we need only 4.5 million people to help out! Yay! (We'll still only get $1.06 cents each, but we can "forget" to pay some people.) Let's start recruiting fellow answerers...everyone reading this, if you get at least twenty people to join in, I'll make sure you get your fair share.

; )

(Wouldn't it be interesting if this question got shut down by Answers personnel? I'd laugh hysterically. For hours. Sixteen hours, actually.)

Ben is right on the "never going to be won" money. But what about the 65 teams? there is that stupid game between #64 and #65 so the total number of outcomes is 2^4 and you have 3.6893e+18 brackets.... good grief.

If anyone is getting into a latter bracket game such as for the Sweet 16 there is a general formula for the number of brackets needed when the number of teams is a power of 2.

64 = 2^6 teams..., 6 rounds needed to determine a champion, there are 2^63 possible brackets

for the 32 = 2^5 teams the survive round 1 there are 5 rounds needed for a champ, there are 2^31 possible brackets

and so on.

the general formula, if there are 2^n teams, there are n rounds and 2^(2^n - 1) different bracket outcomes

Good luck with the predictions. At least sports is a completely random event.

Yahoo does not run a lottery. Such emails are designed to either steal your ID/credit information and/or have you send in money to "process the claim" or whatever other way the scammers word. The truth is there is no lottery and there is no prize money.

I Believe That It's Not A Game.

to win, you have to pick correctly the results of 63 games.

2^63/5

HAHA I JUST STOLE THE OTHER GUYS ANSWER:

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Half an hour with no solutions? I'm flabbergasted.

= ^ )

We already have the 64 teams arranged in their starting positions of the bracket. So our first decisions come with the first round of games, of which there are 32. Each game has two decisions we need to make. Similarly for the second round, there are 16 games, each game has 2 choices (we're certainly not going to choose one of the teams we've decided earlier will lose). Continuing, we end up with a total of

1+2+4+8+16+32 = 63

games, each with two choices for us to make, so

2^(63)

different brackets we could fill out. Dividing this by 5 will give you the number of screen names you need to guarantee the 5mil. My calculator, surprisingly, can do this out, and it would appear we need approximately 1.845*10^(18), or 1.845 quintillion screen names.

Let's keep going with this. I estimate it should take you, say, 30 seconds to create each screen name (without computer aid, and without messing up any of the forms). Then perhaps another 2 minutes to fill in a bracket (I have no idea how yahoo wants those entered...).

So every 5 brackets takes you about 10.5 minutes. Then we need

1.845 * 10^(18) * 10.5 / 60 = 3.228 * 10^(17)

or 322.8 quadrillion hours...we have about 18.5 hours at the time of posting this before tip-off. We seem to be a bit short of time.

Perhaps more later...how many people would it take helping, what kind of probabilities we have, etc...

EDIT: I'd be happy to join in the efforts, for my share of the profit. Perhaps others would do the same. Let's see how many people we would need in order to get it done in the 16 hours we have left (at the time of this edit).

We've already decided a total of about 322.8 quadrillion hours need to be put in. Dividing this by the number of helpers will give us our total number of working hours, which needs to be at most 16. Thus, we need

322.8quad / 16 = 2.018*10^(16)

or 20.18 quadrillion people. There are what, 6.6 billion people on the planet right now? So we're a factor of 3 million shy of our goal, and we would each earn well under a penny if we divided up the 5mil evenly. Perhaps we should have started planning earlier?

Let's see...the first games tend to have pretty good odds in favor of one team or the other, so let's just go with the odds on those. Then we have only 31 games to choose our favorites, for 2^31 choices. Then we need only have 429,496,730 yahoo accounts, for about 75,161,928 hours of work. Dividing again by 16 hours remaining, and we need only 4.5 million people to help out! Yay! (We'll still only get $1.06 cents each, but we can "forget" to pay some people.) Let's start recruiting fellow answerers...everyone reading this, if you get at least twenty people to join in, I'll make sure you get your fair share.

; )

(Wouldn't it be interesting if this question got shut down by Answers personnel? I'd laugh hysterically. For hours. Sixteen hours, actually.)

ive done that before

a lot

that looks difficult.....