Find $5$ numbers where the sum of all pairs gives the results $110, 112, 113, 114, 115, 116, 117, 118, 120,...












4












$begingroup$



Find $5$ numbers where the sum of the pairs gives the results $110, 112, 113, 114, 115, 116, 117, 118, 120, 121$




I have been trying on this question for some time and it seems easy at first glance, but later on, I was unable to start on the question. I tried turning these into equations with $a_1, a_2, a_3, a_4, text{ and }a_5$ but couldn't as it is not determined which $2$ numbers give which sum. I was, however, able to achieve that $a_1+a_2+a_3+a_4+a_5=289$ (which is obvious). Now is there anyway I could continue without guessing. Thank you.










share|cite|improve this question









$endgroup$

















    4












    $begingroup$



    Find $5$ numbers where the sum of the pairs gives the results $110, 112, 113, 114, 115, 116, 117, 118, 120, 121$




    I have been trying on this question for some time and it seems easy at first glance, but later on, I was unable to start on the question. I tried turning these into equations with $a_1, a_2, a_3, a_4, text{ and }a_5$ but couldn't as it is not determined which $2$ numbers give which sum. I was, however, able to achieve that $a_1+a_2+a_3+a_4+a_5=289$ (which is obvious). Now is there anyway I could continue without guessing. Thank you.










    share|cite|improve this question









    $endgroup$















      4












      4








      4





      $begingroup$



      Find $5$ numbers where the sum of the pairs gives the results $110, 112, 113, 114, 115, 116, 117, 118, 120, 121$




      I have been trying on this question for some time and it seems easy at first glance, but later on, I was unable to start on the question. I tried turning these into equations with $a_1, a_2, a_3, a_4, text{ and }a_5$ but couldn't as it is not determined which $2$ numbers give which sum. I was, however, able to achieve that $a_1+a_2+a_3+a_4+a_5=289$ (which is obvious). Now is there anyway I could continue without guessing. Thank you.










      share|cite|improve this question









      $endgroup$





      Find $5$ numbers where the sum of the pairs gives the results $110, 112, 113, 114, 115, 116, 117, 118, 120, 121$




      I have been trying on this question for some time and it seems easy at first glance, but later on, I was unable to start on the question. I tried turning these into equations with $a_1, a_2, a_3, a_4, text{ and }a_5$ but couldn't as it is not determined which $2$ numbers give which sum. I was, however, able to achieve that $a_1+a_2+a_3+a_4+a_5=289$ (which is obvious). Now is there anyway I could continue without guessing. Thank you.







      elementary-number-theory






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Dec 8 '18 at 11:40









      user587054user587054

      56511




      56511






















          1 Answer
          1






          active

          oldest

          votes


















          5












          $begingroup$

          As there are no duplicates among the pair sums, the five numbers are distinct. So wlog. $a_1<a_2<a_3<a_4<a_5$. Then $110=a_1+a_2$, $112=a_1+a_3$, which makes $a_3=a_2+2$. Similarly, we find $a_4=a_3+1$ from the last two entries $120,121$. So far we have found that the numbers are
          $$a_1, a_2, a_2+2, a_2+3, a_5.$$
          This also tells us that $a_1+a_4=113$ and that $a_2+a_5=118$.
          Now that the three pair sums $a_2+a_3=2a_2+2$, $a_2+a_4=2a_2+3$, $a_3+a_4=2a_2+5$ must occur among $114,115,116,117$. The only possible match is that $a_2+a_3=114$, i.e., $a_2=56$. The rest follows easily from here.






          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%2f3031002%2ffind-5-numbers-where-the-sum-of-all-pairs-gives-the-results-110-112-113-11%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









            5












            $begingroup$

            As there are no duplicates among the pair sums, the five numbers are distinct. So wlog. $a_1<a_2<a_3<a_4<a_5$. Then $110=a_1+a_2$, $112=a_1+a_3$, which makes $a_3=a_2+2$. Similarly, we find $a_4=a_3+1$ from the last two entries $120,121$. So far we have found that the numbers are
            $$a_1, a_2, a_2+2, a_2+3, a_5.$$
            This also tells us that $a_1+a_4=113$ and that $a_2+a_5=118$.
            Now that the three pair sums $a_2+a_3=2a_2+2$, $a_2+a_4=2a_2+3$, $a_3+a_4=2a_2+5$ must occur among $114,115,116,117$. The only possible match is that $a_2+a_3=114$, i.e., $a_2=56$. The rest follows easily from here.






            share|cite|improve this answer









            $endgroup$


















              5












              $begingroup$

              As there are no duplicates among the pair sums, the five numbers are distinct. So wlog. $a_1<a_2<a_3<a_4<a_5$. Then $110=a_1+a_2$, $112=a_1+a_3$, which makes $a_3=a_2+2$. Similarly, we find $a_4=a_3+1$ from the last two entries $120,121$. So far we have found that the numbers are
              $$a_1, a_2, a_2+2, a_2+3, a_5.$$
              This also tells us that $a_1+a_4=113$ and that $a_2+a_5=118$.
              Now that the three pair sums $a_2+a_3=2a_2+2$, $a_2+a_4=2a_2+3$, $a_3+a_4=2a_2+5$ must occur among $114,115,116,117$. The only possible match is that $a_2+a_3=114$, i.e., $a_2=56$. The rest follows easily from here.






              share|cite|improve this answer









              $endgroup$
















                5












                5








                5





                $begingroup$

                As there are no duplicates among the pair sums, the five numbers are distinct. So wlog. $a_1<a_2<a_3<a_4<a_5$. Then $110=a_1+a_2$, $112=a_1+a_3$, which makes $a_3=a_2+2$. Similarly, we find $a_4=a_3+1$ from the last two entries $120,121$. So far we have found that the numbers are
                $$a_1, a_2, a_2+2, a_2+3, a_5.$$
                This also tells us that $a_1+a_4=113$ and that $a_2+a_5=118$.
                Now that the three pair sums $a_2+a_3=2a_2+2$, $a_2+a_4=2a_2+3$, $a_3+a_4=2a_2+5$ must occur among $114,115,116,117$. The only possible match is that $a_2+a_3=114$, i.e., $a_2=56$. The rest follows easily from here.






                share|cite|improve this answer









                $endgroup$



                As there are no duplicates among the pair sums, the five numbers are distinct. So wlog. $a_1<a_2<a_3<a_4<a_5$. Then $110=a_1+a_2$, $112=a_1+a_3$, which makes $a_3=a_2+2$. Similarly, we find $a_4=a_3+1$ from the last two entries $120,121$. So far we have found that the numbers are
                $$a_1, a_2, a_2+2, a_2+3, a_5.$$
                This also tells us that $a_1+a_4=113$ and that $a_2+a_5=118$.
                Now that the three pair sums $a_2+a_3=2a_2+2$, $a_2+a_4=2a_2+3$, $a_3+a_4=2a_2+5$ must occur among $114,115,116,117$. The only possible match is that $a_2+a_3=114$, i.e., $a_2=56$. The rest follows easily from here.







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Dec 8 '18 at 11:56









                Hagen von EitzenHagen von Eitzen

                282k23272507




                282k23272507






























                    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%2f3031002%2ffind-5-numbers-where-the-sum-of-all-pairs-gives-the-results-110-112-113-11%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

                    Biblatex bibliography style without URLs when DOI exists (in Overleaf with Zotero bibliography)

                    ComboBox Display Member on multiple fields

                    Is it possible to collect Nectar points via Trainline?