Probability of multiple trials?
$begingroup$
give an event $E$ and probability that event occurs as P. If it was attempted $1000$ times. What would be the answers to the following question.
- probability of at least the event occurring one time ? is it $1-(1-P)^{1000}$
- probability of at most the event occurring one time? is it $P*(1-P)^{999}$
- probability of at least the event occurring three times? is it $P^3*(1-(1-P)^{997})$
- probability of at most the event occurring three times ? is it $P^3*(1-P)^{997}$
- probability of event occurring more than one time ? is it $P^2*(1-(1-P)^{998})$
- probability of event not occurring at all ? is it $(1-p)^{1000}$
probability probability-theory
$endgroup$
|
show 7 more comments
$begingroup$
give an event $E$ and probability that event occurs as P. If it was attempted $1000$ times. What would be the answers to the following question.
- probability of at least the event occurring one time ? is it $1-(1-P)^{1000}$
- probability of at most the event occurring one time? is it $P*(1-P)^{999}$
- probability of at least the event occurring three times? is it $P^3*(1-(1-P)^{997})$
- probability of at most the event occurring three times ? is it $P^3*(1-P)^{997}$
- probability of event occurring more than one time ? is it $P^2*(1-(1-P)^{998})$
- probability of event not occurring at all ? is it $(1-p)^{1000}$
probability probability-theory
$endgroup$
1
$begingroup$
"$-3$ down vote favorite"....did you cut and paste this from another question on this site?
$endgroup$
– lulu
Oct 3 '17 at 11:51
$begingroup$
What have you tried? These are all basic questions in the use of the binomial distribution
$endgroup$
– lulu
Oct 3 '17 at 11:53
$begingroup$
@lulu. Yea it was 1st posted at mathoverflow. And as for your question i have just started to learn Probability.So these are some of the questions that has popped in to my mind
$endgroup$
– user119020
Oct 3 '17 at 12:08
1
$begingroup$
Well, the second one is wrong. Let $P_i$ be the probability that it occurs exactly $i$ times, so you want $P_0+P_1$. As you point out $P_0=(1-p)^{1000}$. From the binomial distribution we get $P_1=1000times ptimes (1-p)^{999}$.
$endgroup$
– lulu
Oct 3 '17 at 23:15
1
$begingroup$
No, I wasn't saying that. Others are wrong along the same lines. For the third, say, we have $P_3=binom {1000}3times p^3times (1-p)^{997}$ and so on.
$endgroup$
– lulu
Oct 4 '17 at 10:59
|
show 7 more comments
$begingroup$
give an event $E$ and probability that event occurs as P. If it was attempted $1000$ times. What would be the answers to the following question.
- probability of at least the event occurring one time ? is it $1-(1-P)^{1000}$
- probability of at most the event occurring one time? is it $P*(1-P)^{999}$
- probability of at least the event occurring three times? is it $P^3*(1-(1-P)^{997})$
- probability of at most the event occurring three times ? is it $P^3*(1-P)^{997}$
- probability of event occurring more than one time ? is it $P^2*(1-(1-P)^{998})$
- probability of event not occurring at all ? is it $(1-p)^{1000}$
probability probability-theory
$endgroup$
give an event $E$ and probability that event occurs as P. If it was attempted $1000$ times. What would be the answers to the following question.
- probability of at least the event occurring one time ? is it $1-(1-P)^{1000}$
- probability of at most the event occurring one time? is it $P*(1-P)^{999}$
- probability of at least the event occurring three times? is it $P^3*(1-(1-P)^{997})$
- probability of at most the event occurring three times ? is it $P^3*(1-P)^{997}$
- probability of event occurring more than one time ? is it $P^2*(1-(1-P)^{998})$
- probability of event not occurring at all ? is it $(1-p)^{1000}$
probability probability-theory
probability probability-theory
edited Oct 4 '17 at 11:53


kimi Tanaka
414411
414411
asked Oct 3 '17 at 11:48
user119020user119020
544
544
1
$begingroup$
"$-3$ down vote favorite"....did you cut and paste this from another question on this site?
$endgroup$
– lulu
Oct 3 '17 at 11:51
$begingroup$
What have you tried? These are all basic questions in the use of the binomial distribution
$endgroup$
– lulu
Oct 3 '17 at 11:53
$begingroup$
@lulu. Yea it was 1st posted at mathoverflow. And as for your question i have just started to learn Probability.So these are some of the questions that has popped in to my mind
$endgroup$
– user119020
Oct 3 '17 at 12:08
1
$begingroup$
Well, the second one is wrong. Let $P_i$ be the probability that it occurs exactly $i$ times, so you want $P_0+P_1$. As you point out $P_0=(1-p)^{1000}$. From the binomial distribution we get $P_1=1000times ptimes (1-p)^{999}$.
$endgroup$
– lulu
Oct 3 '17 at 23:15
1
$begingroup$
No, I wasn't saying that. Others are wrong along the same lines. For the third, say, we have $P_3=binom {1000}3times p^3times (1-p)^{997}$ and so on.
$endgroup$
– lulu
Oct 4 '17 at 10:59
|
show 7 more comments
1
$begingroup$
"$-3$ down vote favorite"....did you cut and paste this from another question on this site?
$endgroup$
– lulu
Oct 3 '17 at 11:51
$begingroup$
What have you tried? These are all basic questions in the use of the binomial distribution
$endgroup$
– lulu
Oct 3 '17 at 11:53
$begingroup$
@lulu. Yea it was 1st posted at mathoverflow. And as for your question i have just started to learn Probability.So these are some of the questions that has popped in to my mind
$endgroup$
– user119020
Oct 3 '17 at 12:08
1
$begingroup$
Well, the second one is wrong. Let $P_i$ be the probability that it occurs exactly $i$ times, so you want $P_0+P_1$. As you point out $P_0=(1-p)^{1000}$. From the binomial distribution we get $P_1=1000times ptimes (1-p)^{999}$.
$endgroup$
– lulu
Oct 3 '17 at 23:15
1
$begingroup$
No, I wasn't saying that. Others are wrong along the same lines. For the third, say, we have $P_3=binom {1000}3times p^3times (1-p)^{997}$ and so on.
$endgroup$
– lulu
Oct 4 '17 at 10:59
1
1
$begingroup$
"$-3$ down vote favorite"....did you cut and paste this from another question on this site?
$endgroup$
– lulu
Oct 3 '17 at 11:51
$begingroup$
"$-3$ down vote favorite"....did you cut and paste this from another question on this site?
$endgroup$
– lulu
Oct 3 '17 at 11:51
$begingroup$
What have you tried? These are all basic questions in the use of the binomial distribution
$endgroup$
– lulu
Oct 3 '17 at 11:53
$begingroup$
What have you tried? These are all basic questions in the use of the binomial distribution
$endgroup$
– lulu
Oct 3 '17 at 11:53
$begingroup$
@lulu. Yea it was 1st posted at mathoverflow. And as for your question i have just started to learn Probability.So these are some of the questions that has popped in to my mind
$endgroup$
– user119020
Oct 3 '17 at 12:08
$begingroup$
@lulu. Yea it was 1st posted at mathoverflow. And as for your question i have just started to learn Probability.So these are some of the questions that has popped in to my mind
$endgroup$
– user119020
Oct 3 '17 at 12:08
1
1
$begingroup$
Well, the second one is wrong. Let $P_i$ be the probability that it occurs exactly $i$ times, so you want $P_0+P_1$. As you point out $P_0=(1-p)^{1000}$. From the binomial distribution we get $P_1=1000times ptimes (1-p)^{999}$.
$endgroup$
– lulu
Oct 3 '17 at 23:15
$begingroup$
Well, the second one is wrong. Let $P_i$ be the probability that it occurs exactly $i$ times, so you want $P_0+P_1$. As you point out $P_0=(1-p)^{1000}$. From the binomial distribution we get $P_1=1000times ptimes (1-p)^{999}$.
$endgroup$
– lulu
Oct 3 '17 at 23:15
1
1
$begingroup$
No, I wasn't saying that. Others are wrong along the same lines. For the third, say, we have $P_3=binom {1000}3times p^3times (1-p)^{997}$ and so on.
$endgroup$
– lulu
Oct 4 '17 at 10:59
$begingroup$
No, I wasn't saying that. Others are wrong along the same lines. For the third, say, we have $P_3=binom {1000}3times p^3times (1-p)^{997}$ and so on.
$endgroup$
– lulu
Oct 4 '17 at 10:59
|
show 7 more comments
2 Answers
2
active
oldest
votes
$begingroup$
Hints:
The probability it happens $k$ times in $n$ independent attempts is $P(k)={n choose k}p^k (1-p)^{n-k}$. Your attempts seem to have ignored the binomial co-efficients which count the different possible orderings of successes.
To answer the questions, consider:
- $1$ minus probability $k=0$
- probability $k=0$ or $k=1$
- probability $k=0$ or $k=1$ or $k=2$ or $k=3$
- $1$ minus probability $k=0$ or $k=1$ or $k=2$
- $1$ minus probability $k=0$ or $k=1$
- probability $k=0$
$endgroup$
add a comment |
$begingroup$
- probability of at least the event occurring one time ? is it $1-(1-P)^{1000}$
You don't have any other way to count the event not occurring in any other way.
The result is $binom{1000}{1000}$$times${$1-(1-P)^{1000}$}
- probability of at most the event occurring one time? is it $P*(1-P)^{999}$
As in Lulu's comment, it has been already explained, you need to consider not occuring and only once the event occurs. Only once the event occurs, you have many other ways to count them such as the way at 1st observaton the event happens and the rest of observations the event not happens or the way at 2nd observations the event does not happen and so on so forth.
The result is altogether not occuring and occring once.
$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$}
- probability of at least the event occurring three times? is it $P^3*(1-(1-P)^{997})$
Now You need to add another scenario the event happens twice to the last one. And you have the probability of at most twice happens. You need to remove them from all the event 1. Now you get the probability of at least three times happens.
$1$ - {$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$} + $binom{1000}{2}$$times$${p^{2}times(1-P)^{998}}$}
- probability of at most the event occurring three times ? is it $P^3*(1-P)^{997}$
You need to add the probaility of three times happen to the probaility of at most twice happen.
$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$} + $binom{1000}{2}$$times$${p^{2}times(1-P)^{998}}$ + $binom{1000}{3}$$times$${p^{3}times(1-P)^{997}}$
- probability of event occurring more than one time ? is it $P^2*(1-(1-P)^{998})$
$1$ - { the probaility of at most the event occuring one time}
- the probability of event not occurring at all ? is it $(1-p)^{1000}$
Yes.
$endgroup$
add a comment |
Your Answer
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f2455685%2fprobability-of-multiple-trials%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Hints:
The probability it happens $k$ times in $n$ independent attempts is $P(k)={n choose k}p^k (1-p)^{n-k}$. Your attempts seem to have ignored the binomial co-efficients which count the different possible orderings of successes.
To answer the questions, consider:
- $1$ minus probability $k=0$
- probability $k=0$ or $k=1$
- probability $k=0$ or $k=1$ or $k=2$ or $k=3$
- $1$ minus probability $k=0$ or $k=1$ or $k=2$
- $1$ minus probability $k=0$ or $k=1$
- probability $k=0$
$endgroup$
add a comment |
$begingroup$
Hints:
The probability it happens $k$ times in $n$ independent attempts is $P(k)={n choose k}p^k (1-p)^{n-k}$. Your attempts seem to have ignored the binomial co-efficients which count the different possible orderings of successes.
To answer the questions, consider:
- $1$ minus probability $k=0$
- probability $k=0$ or $k=1$
- probability $k=0$ or $k=1$ or $k=2$ or $k=3$
- $1$ minus probability $k=0$ or $k=1$ or $k=2$
- $1$ minus probability $k=0$ or $k=1$
- probability $k=0$
$endgroup$
add a comment |
$begingroup$
Hints:
The probability it happens $k$ times in $n$ independent attempts is $P(k)={n choose k}p^k (1-p)^{n-k}$. Your attempts seem to have ignored the binomial co-efficients which count the different possible orderings of successes.
To answer the questions, consider:
- $1$ minus probability $k=0$
- probability $k=0$ or $k=1$
- probability $k=0$ or $k=1$ or $k=2$ or $k=3$
- $1$ minus probability $k=0$ or $k=1$ or $k=2$
- $1$ minus probability $k=0$ or $k=1$
- probability $k=0$
$endgroup$
Hints:
The probability it happens $k$ times in $n$ independent attempts is $P(k)={n choose k}p^k (1-p)^{n-k}$. Your attempts seem to have ignored the binomial co-efficients which count the different possible orderings of successes.
To answer the questions, consider:
- $1$ minus probability $k=0$
- probability $k=0$ or $k=1$
- probability $k=0$ or $k=1$ or $k=2$ or $k=3$
- $1$ minus probability $k=0$ or $k=1$ or $k=2$
- $1$ minus probability $k=0$ or $k=1$
- probability $k=0$
answered Oct 4 '17 at 12:16
HenryHenry
101k482170
101k482170
add a comment |
add a comment |
$begingroup$
- probability of at least the event occurring one time ? is it $1-(1-P)^{1000}$
You don't have any other way to count the event not occurring in any other way.
The result is $binom{1000}{1000}$$times${$1-(1-P)^{1000}$}
- probability of at most the event occurring one time? is it $P*(1-P)^{999}$
As in Lulu's comment, it has been already explained, you need to consider not occuring and only once the event occurs. Only once the event occurs, you have many other ways to count them such as the way at 1st observaton the event happens and the rest of observations the event not happens or the way at 2nd observations the event does not happen and so on so forth.
The result is altogether not occuring and occring once.
$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$}
- probability of at least the event occurring three times? is it $P^3*(1-(1-P)^{997})$
Now You need to add another scenario the event happens twice to the last one. And you have the probability of at most twice happens. You need to remove them from all the event 1. Now you get the probability of at least three times happens.
$1$ - {$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$} + $binom{1000}{2}$$times$${p^{2}times(1-P)^{998}}$}
- probability of at most the event occurring three times ? is it $P^3*(1-P)^{997}$
You need to add the probaility of three times happen to the probaility of at most twice happen.
$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$} + $binom{1000}{2}$$times$${p^{2}times(1-P)^{998}}$ + $binom{1000}{3}$$times$${p^{3}times(1-P)^{997}}$
- probability of event occurring more than one time ? is it $P^2*(1-(1-P)^{998})$
$1$ - { the probaility of at most the event occuring one time}
- the probability of event not occurring at all ? is it $(1-p)^{1000}$
Yes.
$endgroup$
add a comment |
$begingroup$
- probability of at least the event occurring one time ? is it $1-(1-P)^{1000}$
You don't have any other way to count the event not occurring in any other way.
The result is $binom{1000}{1000}$$times${$1-(1-P)^{1000}$}
- probability of at most the event occurring one time? is it $P*(1-P)^{999}$
As in Lulu's comment, it has been already explained, you need to consider not occuring and only once the event occurs. Only once the event occurs, you have many other ways to count them such as the way at 1st observaton the event happens and the rest of observations the event not happens or the way at 2nd observations the event does not happen and so on so forth.
The result is altogether not occuring and occring once.
$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$}
- probability of at least the event occurring three times? is it $P^3*(1-(1-P)^{997})$
Now You need to add another scenario the event happens twice to the last one. And you have the probability of at most twice happens. You need to remove them from all the event 1. Now you get the probability of at least three times happens.
$1$ - {$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$} + $binom{1000}{2}$$times$${p^{2}times(1-P)^{998}}$}
- probability of at most the event occurring three times ? is it $P^3*(1-P)^{997}$
You need to add the probaility of three times happen to the probaility of at most twice happen.
$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$} + $binom{1000}{2}$$times$${p^{2}times(1-P)^{998}}$ + $binom{1000}{3}$$times$${p^{3}times(1-P)^{997}}$
- probability of event occurring more than one time ? is it $P^2*(1-(1-P)^{998})$
$1$ - { the probaility of at most the event occuring one time}
- the probability of event not occurring at all ? is it $(1-p)^{1000}$
Yes.
$endgroup$
add a comment |
$begingroup$
- probability of at least the event occurring one time ? is it $1-(1-P)^{1000}$
You don't have any other way to count the event not occurring in any other way.
The result is $binom{1000}{1000}$$times${$1-(1-P)^{1000}$}
- probability of at most the event occurring one time? is it $P*(1-P)^{999}$
As in Lulu's comment, it has been already explained, you need to consider not occuring and only once the event occurs. Only once the event occurs, you have many other ways to count them such as the way at 1st observaton the event happens and the rest of observations the event not happens or the way at 2nd observations the event does not happen and so on so forth.
The result is altogether not occuring and occring once.
$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$}
- probability of at least the event occurring three times? is it $P^3*(1-(1-P)^{997})$
Now You need to add another scenario the event happens twice to the last one. And you have the probability of at most twice happens. You need to remove them from all the event 1. Now you get the probability of at least three times happens.
$1$ - {$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$} + $binom{1000}{2}$$times$${p^{2}times(1-P)^{998}}$}
- probability of at most the event occurring three times ? is it $P^3*(1-P)^{997}$
You need to add the probaility of three times happen to the probaility of at most twice happen.
$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$} + $binom{1000}{2}$$times$${p^{2}times(1-P)^{998}}$ + $binom{1000}{3}$$times$${p^{3}times(1-P)^{997}}$
- probability of event occurring more than one time ? is it $P^2*(1-(1-P)^{998})$
$1$ - { the probaility of at most the event occuring one time}
- the probability of event not occurring at all ? is it $(1-p)^{1000}$
Yes.
$endgroup$
- probability of at least the event occurring one time ? is it $1-(1-P)^{1000}$
You don't have any other way to count the event not occurring in any other way.
The result is $binom{1000}{1000}$$times${$1-(1-P)^{1000}$}
- probability of at most the event occurring one time? is it $P*(1-P)^{999}$
As in Lulu's comment, it has been already explained, you need to consider not occuring and only once the event occurs. Only once the event occurs, you have many other ways to count them such as the way at 1st observaton the event happens and the rest of observations the event not happens or the way at 2nd observations the event does not happen and so on so forth.
The result is altogether not occuring and occring once.
$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$}
- probability of at least the event occurring three times? is it $P^3*(1-(1-P)^{997})$
Now You need to add another scenario the event happens twice to the last one. And you have the probability of at most twice happens. You need to remove them from all the event 1. Now you get the probability of at least three times happens.
$1$ - {$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$} + $binom{1000}{2}$$times$${p^{2}times(1-P)^{998}}$}
- probability of at most the event occurring three times ? is it $P^3*(1-P)^{997}$
You need to add the probaility of three times happen to the probaility of at most twice happen.
$binom{1000}{1000}$$times${$1-(1-P)^{1000}$} + $binom{1000}{1}$$times${$ptimes(1-P)^{999}$} + $binom{1000}{2}$$times$${p^{2}times(1-P)^{998}}$ + $binom{1000}{3}$$times$${p^{3}times(1-P)^{997}}$
- probability of event occurring more than one time ? is it $P^2*(1-(1-P)^{998})$
$1$ - { the probaility of at most the event occuring one time}
- the probability of event not occurring at all ? is it $(1-p)^{1000}$
Yes.
answered Oct 4 '17 at 12:59


kimi Tanakakimi Tanaka
414411
414411
add a comment |
add a comment |
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f2455685%2fprobability-of-multiple-trials%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
1
$begingroup$
"$-3$ down vote favorite"....did you cut and paste this from another question on this site?
$endgroup$
– lulu
Oct 3 '17 at 11:51
$begingroup$
What have you tried? These are all basic questions in the use of the binomial distribution
$endgroup$
– lulu
Oct 3 '17 at 11:53
$begingroup$
@lulu. Yea it was 1st posted at mathoverflow. And as for your question i have just started to learn Probability.So these are some of the questions that has popped in to my mind
$endgroup$
– user119020
Oct 3 '17 at 12:08
1
$begingroup$
Well, the second one is wrong. Let $P_i$ be the probability that it occurs exactly $i$ times, so you want $P_0+P_1$. As you point out $P_0=(1-p)^{1000}$. From the binomial distribution we get $P_1=1000times ptimes (1-p)^{999}$.
$endgroup$
– lulu
Oct 3 '17 at 23:15
1
$begingroup$
No, I wasn't saying that. Others are wrong along the same lines. For the third, say, we have $P_3=binom {1000}3times p^3times (1-p)^{997}$ and so on.
$endgroup$
– lulu
Oct 4 '17 at 10:59