Find a value for a specific conditional probability












0












$begingroup$


So I'm given an assignment in probability that states the following:



One system is made out of 2 modules. The first module has an error with a probability of 0.4 and the second one with a probability of 0.2 independent from the first module. If there is an error only in the first module(there isn't an error in the second one) the system will not function with a probability of 0.6. For the second module that probability is 0.7. If there is an error in the two modules the system will not function with a probability of 0.8.



-Lets assume that the system is functioning. Find the probability that there isn't an error in both of the modules.



So judging by the assignment here's what I came up with:



A - The first module has an error



B - The second module has an error



M - The system is not functioning




$P(A) = 0.4$ $P(B) = 0.2$ $P(A`) = 0.6$ $P(B`) = 0.8$




$P(M|AB') = 0.6$ $P(M|A`B) = 0.7$ $P(M|AB)=0.8$



Using the law of total probability I've managed to calculate P ( M ) = 0.34 and P( M` ) = 0.66. Now for the actual assignment I need to find:




$ P(A`B`|M`) = frac{P(A`)P(B`)P(M`|A`B`)}{P(M`)}$ $(Using$ $Bayes'$ $ formula)$



However I have no idea how to find $P(M`|A`B`)$.



Any ideas?










share|cite|improve this question











$endgroup$












  • $begingroup$
    The problem doesn't say, so far as I can see. However, you're looking for the probability that the system functions if neither module is in error, and I suspect you are supposed to assume that is $1.$ If I were doing the assignment, that's what I would assume, and I would include a note to that effect.
    $endgroup$
    – saulspatz
    Jan 28 at 19:52
















0












$begingroup$


So I'm given an assignment in probability that states the following:



One system is made out of 2 modules. The first module has an error with a probability of 0.4 and the second one with a probability of 0.2 independent from the first module. If there is an error only in the first module(there isn't an error in the second one) the system will not function with a probability of 0.6. For the second module that probability is 0.7. If there is an error in the two modules the system will not function with a probability of 0.8.



-Lets assume that the system is functioning. Find the probability that there isn't an error in both of the modules.



So judging by the assignment here's what I came up with:



A - The first module has an error



B - The second module has an error



M - The system is not functioning




$P(A) = 0.4$ $P(B) = 0.2$ $P(A`) = 0.6$ $P(B`) = 0.8$




$P(M|AB') = 0.6$ $P(M|A`B) = 0.7$ $P(M|AB)=0.8$



Using the law of total probability I've managed to calculate P ( M ) = 0.34 and P( M` ) = 0.66. Now for the actual assignment I need to find:




$ P(A`B`|M`) = frac{P(A`)P(B`)P(M`|A`B`)}{P(M`)}$ $(Using$ $Bayes'$ $ formula)$



However I have no idea how to find $P(M`|A`B`)$.



Any ideas?










share|cite|improve this question











$endgroup$












  • $begingroup$
    The problem doesn't say, so far as I can see. However, you're looking for the probability that the system functions if neither module is in error, and I suspect you are supposed to assume that is $1.$ If I were doing the assignment, that's what I would assume, and I would include a note to that effect.
    $endgroup$
    – saulspatz
    Jan 28 at 19:52














0












0








0





$begingroup$


So I'm given an assignment in probability that states the following:



One system is made out of 2 modules. The first module has an error with a probability of 0.4 and the second one with a probability of 0.2 independent from the first module. If there is an error only in the first module(there isn't an error in the second one) the system will not function with a probability of 0.6. For the second module that probability is 0.7. If there is an error in the two modules the system will not function with a probability of 0.8.



-Lets assume that the system is functioning. Find the probability that there isn't an error in both of the modules.



So judging by the assignment here's what I came up with:



A - The first module has an error



B - The second module has an error



M - The system is not functioning




$P(A) = 0.4$ $P(B) = 0.2$ $P(A`) = 0.6$ $P(B`) = 0.8$




$P(M|AB') = 0.6$ $P(M|A`B) = 0.7$ $P(M|AB)=0.8$



Using the law of total probability I've managed to calculate P ( M ) = 0.34 and P( M` ) = 0.66. Now for the actual assignment I need to find:




$ P(A`B`|M`) = frac{P(A`)P(B`)P(M`|A`B`)}{P(M`)}$ $(Using$ $Bayes'$ $ formula)$



However I have no idea how to find $P(M`|A`B`)$.



Any ideas?










share|cite|improve this question











$endgroup$




So I'm given an assignment in probability that states the following:



One system is made out of 2 modules. The first module has an error with a probability of 0.4 and the second one with a probability of 0.2 independent from the first module. If there is an error only in the first module(there isn't an error in the second one) the system will not function with a probability of 0.6. For the second module that probability is 0.7. If there is an error in the two modules the system will not function with a probability of 0.8.



-Lets assume that the system is functioning. Find the probability that there isn't an error in both of the modules.



So judging by the assignment here's what I came up with:



A - The first module has an error



B - The second module has an error



M - The system is not functioning




$P(A) = 0.4$ $P(B) = 0.2$ $P(A`) = 0.6$ $P(B`) = 0.8$




$P(M|AB') = 0.6$ $P(M|A`B) = 0.7$ $P(M|AB)=0.8$



Using the law of total probability I've managed to calculate P ( M ) = 0.34 and P( M` ) = 0.66. Now for the actual assignment I need to find:




$ P(A`B`|M`) = frac{P(A`)P(B`)P(M`|A`B`)}{P(M`)}$ $(Using$ $Bayes'$ $ formula)$



However I have no idea how to find $P(M`|A`B`)$.



Any ideas?







probability conditional-probability






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Jan 28 at 19:55







David Mason

















asked Jan 28 at 19:38









David MasonDavid Mason

587




587












  • $begingroup$
    The problem doesn't say, so far as I can see. However, you're looking for the probability that the system functions if neither module is in error, and I suspect you are supposed to assume that is $1.$ If I were doing the assignment, that's what I would assume, and I would include a note to that effect.
    $endgroup$
    – saulspatz
    Jan 28 at 19:52


















  • $begingroup$
    The problem doesn't say, so far as I can see. However, you're looking for the probability that the system functions if neither module is in error, and I suspect you are supposed to assume that is $1.$ If I were doing the assignment, that's what I would assume, and I would include a note to that effect.
    $endgroup$
    – saulspatz
    Jan 28 at 19:52
















$begingroup$
The problem doesn't say, so far as I can see. However, you're looking for the probability that the system functions if neither module is in error, and I suspect you are supposed to assume that is $1.$ If I were doing the assignment, that's what I would assume, and I would include a note to that effect.
$endgroup$
– saulspatz
Jan 28 at 19:52




$begingroup$
The problem doesn't say, so far as I can see. However, you're looking for the probability that the system functions if neither module is in error, and I suspect you are supposed to assume that is $1.$ If I were doing the assignment, that's what I would assume, and I would include a note to that effect.
$endgroup$
– saulspatz
Jan 28 at 19:52










0






active

oldest

votes












Your Answer





StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");

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
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3091299%2ffind-a-value-for-a-specific-conditional-probability%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























0






active

oldest

votes








0






active

oldest

votes









active

oldest

votes






active

oldest

votes
















draft saved

draft discarded




















































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.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3091299%2ffind-a-value-for-a-specific-conditional-probability%23new-answer', 'question_page');
}
);

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







Popular posts from this blog

'app-layout' is not a known element: how to share Component with different Modules

android studio warns about leanback feature tag usage required on manifest while using Unity exported app?

WPF add header to Image with URL pettitions [duplicate]