Probability that at least 1 machine breaks down












1












$begingroup$


In the manufactoring plant of a company two large production machines are used. Machine A breaks down with probability of 0.01, whereas a breakdown of machine B occurs with probability 0.005. Further, if machine A breaks down the probability of a breakdown of machine B is equal to 0.1. What is the probability that the production stops, i.e. at least one of the production machines breaks down?



Basically, my solution so far is:

C - event of interest where at least one production machine breaks down (=1-C¬)

C¬ - complement of C, aka production doesn't stop as no machines break down



P(A) = 0.01 ==> P(A¬) = 1-0.01=0.99

P(B) = 0.005 ==> P(B¬) = 1-0.005 = 0.995

P(C¬)=P(A¬)*P(B¬)=0.98505 chance that no machine will break down



==> 1 - 0.98505 = 0.01495 chance that at least 1 machine will break down and production will stop



However, I feel like I'm missing something because this solutions seems just too easy and I don't know what is P(BlA)=0.1 given for (from: "Further, if machine A breaks down the probability of a breakdown of machine B is equal to 0.1")



Any insight will be much appreciated. Thank you in advance!










share|cite|improve this question









$endgroup$








  • 1




    $begingroup$
    Please, read the MSE $texttt{MathJax}$ Basic Tutorial and Quick Reference. Thanks.
    $endgroup$
    – Felix Marin
    Dec 11 '18 at 16:25












  • $begingroup$
    This approach looks fine to me.
    $endgroup$
    – Warren Hill
    Dec 11 '18 at 16:53










  • $begingroup$
    We have P(B) << P(A). So the final probability will depend majorly on P(A). So we can see that the final answer = 1 - (P(A) + P(B)) which is approximately equal to P(A) = 0.01
    $endgroup$
    – Sagnik
    Dec 11 '18 at 17:18


















1












$begingroup$


In the manufactoring plant of a company two large production machines are used. Machine A breaks down with probability of 0.01, whereas a breakdown of machine B occurs with probability 0.005. Further, if machine A breaks down the probability of a breakdown of machine B is equal to 0.1. What is the probability that the production stops, i.e. at least one of the production machines breaks down?



Basically, my solution so far is:

C - event of interest where at least one production machine breaks down (=1-C¬)

C¬ - complement of C, aka production doesn't stop as no machines break down



P(A) = 0.01 ==> P(A¬) = 1-0.01=0.99

P(B) = 0.005 ==> P(B¬) = 1-0.005 = 0.995

P(C¬)=P(A¬)*P(B¬)=0.98505 chance that no machine will break down



==> 1 - 0.98505 = 0.01495 chance that at least 1 machine will break down and production will stop



However, I feel like I'm missing something because this solutions seems just too easy and I don't know what is P(BlA)=0.1 given for (from: "Further, if machine A breaks down the probability of a breakdown of machine B is equal to 0.1")



Any insight will be much appreciated. Thank you in advance!










share|cite|improve this question









$endgroup$








  • 1




    $begingroup$
    Please, read the MSE $texttt{MathJax}$ Basic Tutorial and Quick Reference. Thanks.
    $endgroup$
    – Felix Marin
    Dec 11 '18 at 16:25












  • $begingroup$
    This approach looks fine to me.
    $endgroup$
    – Warren Hill
    Dec 11 '18 at 16:53










  • $begingroup$
    We have P(B) << P(A). So the final probability will depend majorly on P(A). So we can see that the final answer = 1 - (P(A) + P(B)) which is approximately equal to P(A) = 0.01
    $endgroup$
    – Sagnik
    Dec 11 '18 at 17:18
















1












1








1





$begingroup$


In the manufactoring plant of a company two large production machines are used. Machine A breaks down with probability of 0.01, whereas a breakdown of machine B occurs with probability 0.005. Further, if machine A breaks down the probability of a breakdown of machine B is equal to 0.1. What is the probability that the production stops, i.e. at least one of the production machines breaks down?



Basically, my solution so far is:

C - event of interest where at least one production machine breaks down (=1-C¬)

C¬ - complement of C, aka production doesn't stop as no machines break down



P(A) = 0.01 ==> P(A¬) = 1-0.01=0.99

P(B) = 0.005 ==> P(B¬) = 1-0.005 = 0.995

P(C¬)=P(A¬)*P(B¬)=0.98505 chance that no machine will break down



==> 1 - 0.98505 = 0.01495 chance that at least 1 machine will break down and production will stop



However, I feel like I'm missing something because this solutions seems just too easy and I don't know what is P(BlA)=0.1 given for (from: "Further, if machine A breaks down the probability of a breakdown of machine B is equal to 0.1")



Any insight will be much appreciated. Thank you in advance!










share|cite|improve this question









$endgroup$




In the manufactoring plant of a company two large production machines are used. Machine A breaks down with probability of 0.01, whereas a breakdown of machine B occurs with probability 0.005. Further, if machine A breaks down the probability of a breakdown of machine B is equal to 0.1. What is the probability that the production stops, i.e. at least one of the production machines breaks down?



Basically, my solution so far is:

C - event of interest where at least one production machine breaks down (=1-C¬)

C¬ - complement of C, aka production doesn't stop as no machines break down



P(A) = 0.01 ==> P(A¬) = 1-0.01=0.99

P(B) = 0.005 ==> P(B¬) = 1-0.005 = 0.995

P(C¬)=P(A¬)*P(B¬)=0.98505 chance that no machine will break down



==> 1 - 0.98505 = 0.01495 chance that at least 1 machine will break down and production will stop



However, I feel like I'm missing something because this solutions seems just too easy and I don't know what is P(BlA)=0.1 given for (from: "Further, if machine A breaks down the probability of a breakdown of machine B is equal to 0.1")



Any insight will be much appreciated. Thank you in advance!







probability statistics






share|cite|improve this question













share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked Dec 11 '18 at 16:22









VRTVRT

957




957








  • 1




    $begingroup$
    Please, read the MSE $texttt{MathJax}$ Basic Tutorial and Quick Reference. Thanks.
    $endgroup$
    – Felix Marin
    Dec 11 '18 at 16:25












  • $begingroup$
    This approach looks fine to me.
    $endgroup$
    – Warren Hill
    Dec 11 '18 at 16:53










  • $begingroup$
    We have P(B) << P(A). So the final probability will depend majorly on P(A). So we can see that the final answer = 1 - (P(A) + P(B)) which is approximately equal to P(A) = 0.01
    $endgroup$
    – Sagnik
    Dec 11 '18 at 17:18
















  • 1




    $begingroup$
    Please, read the MSE $texttt{MathJax}$ Basic Tutorial and Quick Reference. Thanks.
    $endgroup$
    – Felix Marin
    Dec 11 '18 at 16:25












  • $begingroup$
    This approach looks fine to me.
    $endgroup$
    – Warren Hill
    Dec 11 '18 at 16:53










  • $begingroup$
    We have P(B) << P(A). So the final probability will depend majorly on P(A). So we can see that the final answer = 1 - (P(A) + P(B)) which is approximately equal to P(A) = 0.01
    $endgroup$
    – Sagnik
    Dec 11 '18 at 17:18










1




1




$begingroup$
Please, read the MSE $texttt{MathJax}$ Basic Tutorial and Quick Reference. Thanks.
$endgroup$
– Felix Marin
Dec 11 '18 at 16:25






$begingroup$
Please, read the MSE $texttt{MathJax}$ Basic Tutorial and Quick Reference. Thanks.
$endgroup$
– Felix Marin
Dec 11 '18 at 16:25














$begingroup$
This approach looks fine to me.
$endgroup$
– Warren Hill
Dec 11 '18 at 16:53




$begingroup$
This approach looks fine to me.
$endgroup$
– Warren Hill
Dec 11 '18 at 16:53












$begingroup$
We have P(B) << P(A). So the final probability will depend majorly on P(A). So we can see that the final answer = 1 - (P(A) + P(B)) which is approximately equal to P(A) = 0.01
$endgroup$
– Sagnik
Dec 11 '18 at 17:18






$begingroup$
We have P(B) << P(A). So the final probability will depend majorly on P(A). So we can see that the final answer = 1 - (P(A) + P(B)) which is approximately equal to P(A) = 0.01
$endgroup$
– Sagnik
Dec 11 '18 at 17:18












1 Answer
1






active

oldest

votes


















1












$begingroup$

You can use the addition rule:
$$begin{align}P(Acup B)&=P(A)+P(B)-P(Acap B)=\
&=0.01+0.005-P(A)cdot P(B|A)=\
&=0.01+0.005-0.01cdot 0.1=\
&=0.014.end{align}$$

Also, note:
$$P(Acap B)=P(A)cdot P(B|A)=P(B)cdot P(A|B).$$






share|cite|improve this answer









$endgroup$













    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%2f3035457%2fprobability-that-at-least-1-machine-breaks-down%23new-answer', 'question_page');
    }
    );

    Post as a guest















    Required, but never shown

























    1 Answer
    1






    active

    oldest

    votes








    1 Answer
    1






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    1












    $begingroup$

    You can use the addition rule:
    $$begin{align}P(Acup B)&=P(A)+P(B)-P(Acap B)=\
    &=0.01+0.005-P(A)cdot P(B|A)=\
    &=0.01+0.005-0.01cdot 0.1=\
    &=0.014.end{align}$$

    Also, note:
    $$P(Acap B)=P(A)cdot P(B|A)=P(B)cdot P(A|B).$$






    share|cite|improve this answer









    $endgroup$


















      1












      $begingroup$

      You can use the addition rule:
      $$begin{align}P(Acup B)&=P(A)+P(B)-P(Acap B)=\
      &=0.01+0.005-P(A)cdot P(B|A)=\
      &=0.01+0.005-0.01cdot 0.1=\
      &=0.014.end{align}$$

      Also, note:
      $$P(Acap B)=P(A)cdot P(B|A)=P(B)cdot P(A|B).$$






      share|cite|improve this answer









      $endgroup$
















        1












        1








        1





        $begingroup$

        You can use the addition rule:
        $$begin{align}P(Acup B)&=P(A)+P(B)-P(Acap B)=\
        &=0.01+0.005-P(A)cdot P(B|A)=\
        &=0.01+0.005-0.01cdot 0.1=\
        &=0.014.end{align}$$

        Also, note:
        $$P(Acap B)=P(A)cdot P(B|A)=P(B)cdot P(A|B).$$






        share|cite|improve this answer









        $endgroup$



        You can use the addition rule:
        $$begin{align}P(Acup B)&=P(A)+P(B)-P(Acap B)=\
        &=0.01+0.005-P(A)cdot P(B|A)=\
        &=0.01+0.005-0.01cdot 0.1=\
        &=0.014.end{align}$$

        Also, note:
        $$P(Acap B)=P(A)cdot P(B|A)=P(B)cdot P(A|B).$$







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Dec 11 '18 at 18:03









        farruhotafarruhota

        20.5k2739




        20.5k2739






























            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%2f3035457%2fprobability-that-at-least-1-machine-breaks-down%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

            Plaza Victoria

            Puebla de Zaragoza

            Musa