Mathematics

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Aug 24, 2021 05:05
Can someone please give a hint for this question?
Aug 24, 2021 05:05
Jul 15, 2021 04:28
Can someone tell how this question should be approached?
Jul 15, 2021 04:27
Let S = {1, 2, 3} be a sample space. Let P be a probability measure defined
on 2S
(the collection of all subsets of S) such that

P(i) = xi
, for i = 1, 2, 3.

Select the correct statement from the following and complete it.
1. (x1, x2, x3) can be any point in a sphere centered at the origin, having
radius R = .
2. (x1, x2, x3) can be any point in a triangle whose vertices are v1 =
, v2 = , and v3 = .
3. (x1, x2, x3) can be any point in a square whose vertices are v1 = ,
v2 = , v3 = , and v4 = .
Jul 5, 2021 09:34
@robjohn But, this computation assumes that we ourselves ask the person setting the question paper (now referred to as paper-setter) "is atleast one of your questions unseen?". However, the question says that we "somehow find out that one of the questions is unseen". Could this not also mean that the paper-setter randomly chooses to talk about one of the questions? In that case the probability would change to 0.6
Jul 5, 2021 06:00
@robjohn
Jul 5, 2021 05:59
Hence
P(B|A) = (0.24 + 0.24)/(0.24 + 0.24 + 0.16)=3/4
Jul 5, 2021 05:59
We are given that

P(su) = P(us) = 0.6 × 0.4 = 0.24

and

P(uu) = 0.4 × 0.4 = 0.16.
Jul 5, 2021 05:59
Thus we need to find the conditional probability of
the event B = {su, us}, that one of the questions on the exam is seen,
given A.

P(B|A) = P(B ∩ A)/P(A)
=
P({su, us})/P({su, uu, us})
Jul 5, 2021 05:58
We are give that at least one of the questions on the exam is unseen,
i.e. the event

A = {su, us, uu}

has taken place.
Jul 5, 2021 05:58
Let the outcomes in the sample space be represented
by two letter words, in which the first letter is ‘s’ if the first question
on the exam is seen and ‘u’ otherwise, and the second letter similarly
describes the second question. Thus the sample space is

S = {su, ss, us, uu}.
Jul 4, 2021 18:13
@robjohn The answer is 3/4, using the Bayes' conditional probability theorem
Jul 4, 2021 12:52
@leslietownes yeah. but the consensus is that answer isn't 1/2
Jul 4, 2021 12:51
should I elaborate further?
Jul 4, 2021 12:50
@leslietownes aka Mr Smith's children
Jul 4, 2021 12:50
The instructor claims that I'm unnecessarily introducing ambiguity where there isn't any. Is that so?
Jul 4, 2021 12:49
But, here, there is a probability that the source of "at least one unseen" had infact only seen the unseen question, but never the whole question paper. This changes the probability of the problem
Jul 4, 2021 12:48
However, I feel that in the boy girl problem, its assumed that the parent knows the gender of both of his kids.
Jul 4, 2021 12:48
This question came in a quiz. When creating the answer key, our teacher referenced the boy girl problem
Jul 4, 2021 12:47
A student has to write an exam in which there are two questions. The
likelihood of any question on the exam being seen before by the student is
60%.
The student finds out somehow that one of the questions on the exam
is an unseen question. What is the probability that the other question has
been seen by the student before?
Jul 4, 2021 12:44
Hello
 

  Basic Mathematics

This room is meant for all basic mathematical discussion, incl...
Jul 15, 2021 18:00
@user21820 It has something to do with P(Sample Space)=1 and that 0<=P(X)<=1
Jul 15, 2021 10:01
It's actually 2^S, representing the powerset of S
Jul 15, 2021 04:28
Can someone tell how this question should be approached?
Jul 15, 2021 04:28
Let S = {1, 2, 3} be a sample space. Let P be a probability measure defined
on 2S
(the collection of all subsets of S) such that

P(i) = xi
, for i = 1, 2, 3.

Select the correct statement from the following and complete it.
1. (x1, x2, x3) can be any point in a sphere centered at the origin, having
radius R = .
2. (x1, x2, x3) can be any point in a triangle whose vertices are v1 =
, v2 = , and v3 = .
3. (x1, x2, x3) can be any point in a square whose vertices are v1 = ,
v2 = , v3 = , and v4 = .
Jul 4, 2021 18:15
@user21820 I'm doing undergrad, but I guess there's still nothing I can do about the issue at hand as she wants a verified source (paper/textbook) :(
Jul 4, 2021 15:52
Is there a way to do that?
Jul 4, 2021 15:51
@user21820 I myself agree on the ambiguity of the question. But the instructor claims that probability word problems are ambiguous by nature and that if I want to claim to the contrary, I need to provide an official citation (paper/some textbook)
Jul 4, 2021 14:45
should I elaborate further?
Jul 4, 2021 14:45
The instructor claims that I'm unnecessarily introducing ambiguity where there isn't any. Is that so?
Jul 4, 2021 14:45
But, here, there is a probability that the source of "at least one unseen" had infact only seen the unseen question, but never the whole question paper. This changes the probability of the problem
Jul 4, 2021 14:45
However, I feel that in the boy girl problem, its assumed that the parent knows the gender of both of his kids.
Jul 4, 2021 14:45
A student has to write an exam in which there are two questions. The
likelihood of any question on the exam being seen before by the student is
60%.
The student finds out somehow that one of the questions on the exam
is an unseen question. What is the probability that the other question has
been seen by the student before?
This question came in a quiz. When creating the answer key, our teacher referenced the boy girl problem
 
Feb 18, 2021 10:15
Bye mate :)
Feb 18, 2021 10:14
Ok. Thanks for your assisstance
Feb 18, 2021 10:11
should we first try streaming a mp4?
Feb 18, 2021 10:10
It didn't play anything either
Feb 18, 2021 10:10
I waited 10 secs and then did Ctrl+C
Feb 18, 2021 10:10
This command doesn't exit
Feb 18, 2021 10:09
$ nc 127.0.0.1 9999 | cvlc -
VLC media player 3.0.12 Vetinari (revision 3.0.12-1-0-gd147bb5e7e)
Feb 18, 2021 10:09
it's a laptop
Feb 18, 2021 10:09
yes
Feb 18, 2021 10:07
I should use that?
Feb 18, 2021 10:06
@Raffa Could you explain what this msg means?
Feb 18, 2021 10:05
This is the vlc log file
Feb 18, 2021 10:05
-- logger module started --
main: Running vlc with the default interface. Use 'cvlc' to use vlc without interface.
mjpeg error: cannot peek
-- logger module stopped --
Feb 18, 2021 10:04
the led was on in all the tests
Feb 18, 2021 10:01
Here's the ffplay output: pastebin.com/iRrNr5mY
Feb 18, 2021 09:47
If I add lirc=no in .mplayer/config, it changes to: pastebin.com/ukNEiemP
Feb 18, 2021 09:45
This is the output of the mplayer command. pastebin.com/4eq4KjQs