to ask if you can answer a question re probability (Maths question)

[Fainne]

So, say I have 20 cards in a pack.

I pick one. It's the Ace of Diamonds let's say for argument's sake.

I then pick another one out of the same pack of 20 cards the following day.

Am I correct in saying that the odds of me picking the same card is a multiple of the single odds?

So 1/20 x 1/20 = 1/400

?

Because I've someone telling me the odds are still 1/20 that I'll pull the same card.

Horse racing and tennis are sports.
I want to win Olympic door opening.

You might win Olympic trolling tbf

If you read the thread you will see people are changing the wording of what I am saying.
While their examples are true, that does not by default make mine wrong.
They are different questions.

@PestyMachtubernahme

I am Schrödinger's newsprintfray.

@mummmy2017:

Will your work not be surprised at you debating maths because you are famously bad at it?

• Question on a test paper. Odds of winning a game show ten times in a row.... Answer. 1/1024*

True, if game show is a coin toss, as coin toss is 50/50.

False, if game show involves opening one of 2 doors where the odds of winning are different for each door.

Question .
When offered a swap do you have to take it?
Answer.
NO this is a free world.

But the odds are better on the swap.
Answer
But you said I could choose.
Oh look I won the door did have a car.

This has been a masterful windup, congrats for stringing it out so long.

Question.

I am arguing about a probability question on the internet. Everyone who disagrees with me seems to be well educated and are giving well thought out and clear explanations to all of my questions.

No-one agrees with me.

What is the probability that I am right?

Think you're on to something there beefthief, nobody could be this obtuse.

So a probability of only two answer over 10 goes, does not come out with 1/1024 for. The same answer each time.
Wow, are you going to tell Oxford uni?

Changing the question again.
Once you open a door, then you are no longer being asked which door did you open. The advantage of knowledge is gone.
You are now being asked did you win a car not.?
There are only two answers to this question.
Go on I dare you tell me the third answer to did you get a car or not.!!!!!!!!

Let me try phrasing it this way.
10 coin flips will have the odds of 1/1024 because the chance of either a head or tail is truly random, there is a 50% chance of it being either a head or tail.

With the door example, at the point the contestant is offered a choice of 2 doors, the outcome is not truly random. One door has twice as much chance of having a car behind it. This changes the chances of winning from 50/50 to 33/66, therefore the betting odds at the outset of the competition will be different.

No the odds won't.
Landlord is only asking do you win or not.
He doesn't care about the door result.
His game is did you get a car or not.
Different question to yours.

Can you really not see that there is a difference between 'did you win a car or not' and 'there's a better chance of winning if you swap'.
It's like the lottery example all over again, if i buy a lottery ticket, i can either win or lose, this does not mean i have a 50% chance of winning the lottery.

But the better chance bit ends once you open the door.
You then progress to did you win.
The question your asking is if you open a door and then swap and win 10 times what are the odds?
I am asking if you go on a show to win a car, what are your chances of 10 wins?

Or to put it (yet) another way.
2 people playing tennis, one a tennis pro, the other a 5 year old. Do you think the odds are 1\1024 of either one winning 10 games in a row? (Bearing in mind the result is either win/lose)
No, because the chances of one of them winning is not truly random.

Your answer is right.
My answer is right.

The chances are not 1 in 1024.
You multiply the chance of winning each time by itself 10 times.

That is GCSE maths

One door is not stronger or older than the other.

"I am asking if you go on a show to win a car, what are your chances of 10 wins?"

You keep changing what you are asking.
But the answer to that particular question, which has already been answered many times, is (2/3)^10. But only if you switch every time. Which you may or may not do, for no discernable reason.

I am asking if you go on a show to win a car, what are your chances of 10 wins?
And the answer is 'it depends on whether you swap or not'.

2.4.8.16, 32.
64, 128, 256, 512, 1024...?

Typo, sorry.
and the answer depends on whether you swap or not.

It would ONLY be 1/1024 if your strategy was to absolutely, at random, choose between the doors whilst ignoring all prior knowledge. You would actually have a better chance of winning more often by doing that...

If you strategy was to always chose your original pick it would be 1/59049
If it was to swap it would be 1024/59049

Oh so if you open the door no car you can swap......wow.