ITT: We discuss the answer to this question

ITT: We discuss the answer to this question.

Math workouts welcome, simulations welcome. What is the answer?

Other urls found in this thread:

en.m.wikipedia.org/wiki/Boy_or_Girl_paradox
engineering.mit.edu/ask/can-computer-generate-truly-random-number
twitter.com/NSFWRedditVideo

oh look it's this thread again

50%

are the coin in same condition?

2 coins flipped, randomly at the same time.

there are 3 results T/H H/T H/H given that and therefore the possibility is 30%?

00
01
10
11

00 never happens
33.33%

But are the coins like brand new? No scrhasc or anything?

50% only h/t and h/h are possible.

i would say ~50%, one is heads ups so its a simply flip using 1 coin.
~50% because it could stand on the edge

no its 50%

00 doesnt happen
01 happens
10 doesnt happen
11 happens

see

Which programming language is this?

>at least one is heads
>AT LEASE ONE

read the problem. Therefore:
HT = happens, at least one heads
HH = happens, at least one heads
TH = happens, at least one heads
TT = doesnt happen

are the coins excactly 100% clone to each other?

vb6

Yes but regardless of which coin lands heads (left or right) they will be one heads one tail. YThats 1 outcome not 2

if one of them is guaranteed fucking heads then you exclude it from the fucking equation

ITS GUARANTEED HEADS SO YOURE ONLY RELYING ON THE OTHER COIN WHICH HAS A 50% CHANCE

OR IS THIS JUST BAIT

What if nigger flip the coins?

What?

If one is heads, the other is heads or tails.
What you need to realise is that the one which is initially heads is also variable, can be either coin. Mathematically it equates to 1/3 chance of happening.

what is your name?`I think I know you. Just use first letter of your name and your surname.

visual basic
>vb6 doesn t hepl m8

Bertrand's box thread went of forever. This probably will too. Answer is 1/3.

If it was what are the chances of both heads with just flipping both, and no more info it would be.
HH
HT
TH
TT
Only one outcome with both heads out of four, so 1/4.

But, since we know AT LEAST one os heads heads we have the three outcomes.
HH
HT
TH
Only one outcome with both heads, so 1/3.

If we knew which coin was one heads, the answer would be 1/2.
If first H, then
HH
HT
So 1/2.
If second H,
HH
TH
Again, one half.

So again, but no one will read this or get it, since we do not know what coin was head, just that one of them was, the answer is 1/3.

There are two coins. either of them can be the guaranteed heads. Don't believe me? Go grab 2 coins, flip them 20 times, and record the results.

Im thinking since im in a stats class that its, 1/1×1/2

PS. For further reading en.m.wikipedia.org/wiki/Boy_or_Girl_paradox

for normies:
Why would it be 33%
>case A: both tails
>case B: both heads
>case C: 1st head 2nd head
>case D: 1st tail 2nd head
>normally all cases had a 25% prob.
If you exclude case A (A=0%),
then the probabilities are shared between B,C,D (100%/3)

fümpfzisch

dubs = t ; t being truth

this is basically, one coin is already heads, flip another to see if that one also lands heads, right?
Since one is already flipped, there is a 50/50 that the other one also lands heads?

everyones saying its 33% yet they havent explained it very well because theyre all autistic

so if it is actually 33% then chance and realistic results are different

no, "two were flipped".
after flipping you are asked blindfolded:
"one of them landed heads" so:
"what is the prob that both landed heads?"

Exactly, you dont know which one was heads initially. It sounds counter intuitive, but if you flip some coins yourself multiple times and work it out, you'll see that you will get at least 1 heads 1/3 of the time.

That's not what is happening. You are flipping both coins at the same time. You don't know what they landed, but some omnipotent force tells you that at least one came up heads. Answer is 1/3 ... described perfectly well so far if you can read.

>one will read this
i got it beforehand, but this explanation is great

>"one of them landed heads"
So it's just the question of the remaining coin which is 50/50, as the other 2 outcomes of the first coin landing the oppsite side are removed.

its 25% or 1/4 that both land heads up.

"What is the probability that both landed heads"

(H,H) (H,T) (T,H) (T,T) = possible outcomes

>both landed heads given at least one of them landed heads

Read the problem

listen troll
1. I got trips 2. you would be right IF the remaining coin was flipped after the one with heads, but it is flipped with the other, thus the probs in question are the probs whil BOTH in the air
3. therefor think again

Read the problem. One coin is already flipped and it's heads.
0 1
0 0
Don't fit the condition of the problem.

1 0
1 1
Do. So it's same as asking about one coin.


0.5

>Ten years compulsory education
>Search is just a tab away
>It's math in a Fatlander thread

Yeah its still 1/4

>flip 2 coins
>chances both land on heads = 1/4
>independent outcomes do not influence each other

the answer is 1/3 since the question asked "what is the probability". probability is basically all possible outcomes, and there are three outcomes

if you tested this in real life you would get HH 50% of the time, but that isnt the question, the question was just asking for the different outcomes, and there are three, TH, HT, and HH

No. One coin is not 'already flipped'. You are flipping both at the same time. Don't believe me? Go flip 20 pairs of coins, and let me know how you go.

It's given doofus.

I've actually gone and flipped 20 pairs of coins myself for real, instead of sitting behind my keyboard like an edgelord such as yourself, and seen that it actually works. Try it!

Yes but you have to remove one of the possibilities as it's not possible for there to be TT making it 1/3 due to one of the coins being a guaranteed heads.

See this doofus
What is given is at least one, AT LEAST ONE, not which specific one.

Explain how the outcome of a flip can be known without flipping a coin.
>you can't.

what is the answer then, and how do i physically test this test

He isnt asking for the outcome, but the chances of a certain outcome. It's called probability, ie: If I flip 2 coins, what are the CHANCES i will get a certain result?

The flipped aren't depending on one another. One is already flipped. Given in the problem. So it's 1/2 probability. Pretty straightforward.

Don't encourage doofuses to try experiments they do not understand, they will miss interpret the results or not do it right. You would either need to have someone there to tell you when the AT LEAST one condition occured, or simply remove all double tail outcomes, then calculate the outcome to get the correct result.

op said given that one landed heads you fag
possibilities are H/T or H/H
50/50

>how do i physically test this test
are you serious..?

Flip. Two. Coins.
x20

record the results each time, then work out the chances.

Another way of saying that would be that two coins are flipped while youre blindfolded, youre told "one of the coins landed heads" and asked "what are the chances the other coin is also heads?"

But it says one is already heads. Already flipped.

You can't use a program to calculat random probabilities though.
Computer program cannot generate truly random results, they are programmed to spread the results of "random" calculations across the spectrum of the tatistics programmed into them.
What that means is that when you use a program to verify the veracity of a statistical claim, it is 100% biased towards how the programmer understood statistics to work.
I may be talking out of my ass but that is how it was explained to me.

can we get a proper math analysis with P(H), P(T), etc.

Pretty simple. It amazes even me that so many people get tricked by this.

two posts are posted one ofter the other, what is the probability that they're both dubs if at least one of them is dubs?

No. Both have already been flipped. That's your hang up here. Both have been flipped, and you are being told AT LEAST one is heads. The question is, what are the chances both are heads.
3 outcomes possible with that given information.
Only one with both heads.
1/3.

You are thinking, one coin flipped came up heads, what's the chance a second coin comes up heads. Completely different situations and questions.

Look I even managed to find someone explaininbg it that knows what the fuck he is talking about
engineering.mit.edu/ask/can-computer-generate-truly-random-number

You actually have to use maths here dipshits, its grade 10 conditional probability.

The probability of event A and B ( two heads) occurring given B (one is heads) is seen through the equation Pr(A|B) = Pr(A unison B)/pr(B)

(1/2 *1/2)/(1/2) = 1/2

No. One is given. It's heads. One does not ask what the probability of an already flipped coin is and their is no mention of a blindfold or closed hand in the problem so it's not flipped yet. Only one coin is given heads. It's just tricking you because the wording is bad.

P(H1) = 0.5
P(H2) = 0.5
P(H2|H1) = P(H2&H1)/P(H1)
P(H1|H2) = P(H1&H2)/P(H1)
P(H1&H2) = 0.5^2 = 0.25
P(H2|H1) = P(H1|H2) = 0.25/0.5 = 0.5
P(H2&H1|H2orH1)=P(H2|H1)+P(H1|H2) = 1
>what problem?

no its (1/2 *1/2)/(1/2)/4 = 1/2

coin flips aren't truly random
for such a simple situation, pseudorandom is good enough

MY RESULTS, and assuming the left coin is always heads
HT HH HH HT HT HH HH HH HT HH HH HH HH HH HH HH HT HH HT HH

THATS DOUBLE HEADS 12/20 FLIPS

REEEEEEEEEEE

( (0.5*0.5) / 0.5 ) / 4
or
(0.5*0.5) / (0.5 / 4)
?
because neither is 1/2

You are solving the question "A coin is flipped, it comes up heads, what is the chance of a second coin being flipped and coming up heads"

That is not the same question as is being asked here.

You seem to understand the maths which is good. Read en.m.wikipedia.org/wiki/Boy_or_Girl_paradox
Especially the psychological investigation section. It explains why this is a bait thread pretty well. This has been bait for far longer than Sup Forums has been around.

>but coins not kids
Then you're a dangus and I'm not going to explain how it's the same problem.

No. It's 1/3 because I say so.

...

oh sorry. i meant
no its (1/2 *1/2)/(1/2)/4-4¤tangent(approx4)'+4 = 1/2. im mathfag.

I never fucking got probabilities
it all just seems arbitrary af

2 coins with 2 faces = 2^2 = 4 possible outcomes. [HH, TH, HT, TT]
Take away the one that doesn't satisfy the predicate. [HH, TH, HT]
Remaining "target" outcome is one out of three possible outcomes.
Chance is 1/3 = 33.33... %

50% since events are independent

you should get more lessons.

/thread

Guaranteed outcome;

HT or TH

Ideal outcome;

HH

2/3 chance for 1 T 1 H, 1/3 chance for HH.

Not. Hard.

Wrong. You need to allocate coin 1 and coin 2, flip them, then record ALL results that have at least one heads, you cant just make one coin heads all the time, that's just 50%, like said in this post:
If you want to do it properly, flip 2 coins seperately, record each result, until you get 20x results with at least ONE of them heads.

Again, you cannot assume which coin is heads. We do not know that, we only know at least one is. To get the right data set you would have to do this again recording all results, remove all TT outcomes, then calculate the result of how many came up HH

i did, just lazyfag

what is not hard? you penis? are you impotent little faggot?

>VB

Die in a fire

on the case of flipping 2 heads
1 1/2 50%
2 1/2 50%

25% chance of flipping 2 heads

TT HT
TH HH

if one coin has landed heads, 50%
HT HH

What a stupid fucking question, OP.

What is a "flip?" A flip must be consistent force, angle, trajectory, etc. Probability equations are fucking retarded because of this. The point of math is to have precise measurements. You cannot do this when the very nature of the Given is flawed.

Very well. See:

Go home physicist

try and follow a more physical approach.

I flip two coins, the first coin lands heads up, before the second coin lands, what are the chances it will land a head? 1/2

If i flip two coins again, instead this time allowing the latter coin of the first statement to land first, revealing heads, what are the chances, before the second coin lands, that its result will grant two heads? 1/2

Somewhat true, but not completely, and you're sort of missing the point on this one anyway. The "quality" of pseudorandom numbers (as generated by a computer) is more than good enough for experiments like this, assuming the algorithm is sound - which, generally, it is.

The "quality" pretty much only really becomes an issue when you start delving into cryptography where poor randomness can cause vulnerabilities. I can't explain what those would look like because I'm not that heavily into crypto theory, but that's the gist of it.

Except is clearly stated that one head is a given.

>Can't even read
>does not understand basic concept like independence

topkek

fake mathematicians need not apply

make way for the truth

A more physical approach would be you flipping two coins then turning away from the table. Your friend says one is heads, what's the chance the other one is heads?

You are answering a different question, you are doing "A coin is flipped, it lands heads, what's the chance of you flipping a second coin and it also landing heads?" 2 different questions with 2 different answers

Oh and which coin is guaranteed heads there buddy? Either of them? That's right, eat a bag of dicks

theorists BTFO

i might be a retard but
how the fuck does this
disprove this

Since mathematicians have started raging against the physicists already; go do a google search for how often in practice a coin does not land on heads or tails (i.e. on its side) - about 1/8000, which isn't really such small odds that you can't factor it into such a simple equation like this.

>complains about real life not being precise enough for actual accurate measurements
>offer theoretical simulation based on probability as solution
>no response back from that edgelord