Suppose you take out a home mortgage for $160000$ at a monthly interest rate of $0.5$%. If you make payments...












2












$begingroup$


Suppose you take out a home mortgage for $160000$ at a monthly interest rate of $0.5$%. If you make payments of $1200$ per month, after how many months will the loan balance be zero. Estimate the answer by graphing the sequence of loan balances and then obtain an exact answer.



I have thought to do the following:



As you have to pay $0.5$% for interest then in the first month you have to pay $0.5$% of $160000=800$ for interest and as you paid for $1200$, then for the house you gave $1200-800=400$, so $160000-400=159600$ was already owed and to know how much is left of the second month one does the same, takes out $0,5$% of $159600=798$ and thus paid interest $798$ and was due $159198$. This reasoning is fine? How can I generalize this and do what they ask of me in the problem? Thank you.










share|cite|improve this question









$endgroup$

















    2












    $begingroup$


    Suppose you take out a home mortgage for $160000$ at a monthly interest rate of $0.5$%. If you make payments of $1200$ per month, after how many months will the loan balance be zero. Estimate the answer by graphing the sequence of loan balances and then obtain an exact answer.



    I have thought to do the following:



    As you have to pay $0.5$% for interest then in the first month you have to pay $0.5$% of $160000=800$ for interest and as you paid for $1200$, then for the house you gave $1200-800=400$, so $160000-400=159600$ was already owed and to know how much is left of the second month one does the same, takes out $0,5$% of $159600=798$ and thus paid interest $798$ and was due $159198$. This reasoning is fine? How can I generalize this and do what they ask of me in the problem? Thank you.










    share|cite|improve this question









    $endgroup$















      2












      2








      2


      1



      $begingroup$


      Suppose you take out a home mortgage for $160000$ at a monthly interest rate of $0.5$%. If you make payments of $1200$ per month, after how many months will the loan balance be zero. Estimate the answer by graphing the sequence of loan balances and then obtain an exact answer.



      I have thought to do the following:



      As you have to pay $0.5$% for interest then in the first month you have to pay $0.5$% of $160000=800$ for interest and as you paid for $1200$, then for the house you gave $1200-800=400$, so $160000-400=159600$ was already owed and to know how much is left of the second month one does the same, takes out $0,5$% of $159600=798$ and thus paid interest $798$ and was due $159198$. This reasoning is fine? How can I generalize this and do what they ask of me in the problem? Thank you.










      share|cite|improve this question









      $endgroup$




      Suppose you take out a home mortgage for $160000$ at a monthly interest rate of $0.5$%. If you make payments of $1200$ per month, after how many months will the loan balance be zero. Estimate the answer by graphing the sequence of loan balances and then obtain an exact answer.



      I have thought to do the following:



      As you have to pay $0.5$% for interest then in the first month you have to pay $0.5$% of $160000=800$ for interest and as you paid for $1200$, then for the house you gave $1200-800=400$, so $160000-400=159600$ was already owed and to know how much is left of the second month one does the same, takes out $0,5$% of $159600=798$ and thus paid interest $798$ and was due $159198$. This reasoning is fine? How can I generalize this and do what they ask of me in the problem? Thank you.







      calculus algebra-precalculus






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Dec 1 '18 at 23:20









      user482152user482152

      987




      987






















          2 Answers
          2






          active

          oldest

          votes


















          1












          $begingroup$

          Let B(n) be the balance at the end of n months.

          B(0) = a = 160,000.

          B(n + 1) = 1.05.B(n) - 1200.



          B(1) is easy to calculate. Calculate B(1) and B(2) to get a sense for B(n) and how complicated it will be. Don't use 160,000, use a to make this clearer.



          All this mortgage stuff is so well known,

          it's on the web, formulas and tables both.






          share|cite|improve this answer









          $endgroup$





















            1












            $begingroup$

            You're doing fine so far. The next step is to try to write it in symbols instead of numbers, so that you can see the pattern easier.



            Let $P_n$ be the amount of the loan outstanding after $n$ months. $P_0$is the amount of the loan after $0$ months, that is, at the beginning, so $P_0=160000.$ Now, if we know $P_n,$ how do we calculate $P_{n+1}?$ You already shown how to do it; take $0.5%$ of subtract that from $1200$, and the subtract the difference from $P_n$ $$
            P_{n+1}=P_n-(1200-.05P_n)=1.05P_n-1200tag{1}$$



            Now write out he same examples you did, but using symbols this time, by repeated applying equation $(1).$
            $$begin{align}
            P_1&=1.005P_0-1200\
            P_2&=1.005P_1-1200=1.005(1.005P_0-1200)-1200 = 1.005^2P_0-1200(1+1.005)\
            P_3&=1.005P_2-1200=1.005^3P_0-1200(1+1.005+1.005^2)\
            &vdots
            end{align}$$



            As to what they want you to do, I'm guessing, because I don't know what tools you have available. I would think they want you to use equation $(1)$ to calculate the various values of $P_n$ perhaps using some computer spreadsheet program, and graph the values of $P_n$ over time, to see when the value first becomes negative, so that the loan has been paid off.



            Then they want you to figure out the general formula for $P_n,$ a try to compute the value of $n$ for which $P_n$ = $0$. This will almost surely not be a whole number.






            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%2f3021974%2fsuppose-you-take-out-a-home-mortgage-for-160000-at-a-monthly-interest-rate-of%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









              1












              $begingroup$

              Let B(n) be the balance at the end of n months.

              B(0) = a = 160,000.

              B(n + 1) = 1.05.B(n) - 1200.



              B(1) is easy to calculate. Calculate B(1) and B(2) to get a sense for B(n) and how complicated it will be. Don't use 160,000, use a to make this clearer.



              All this mortgage stuff is so well known,

              it's on the web, formulas and tables both.






              share|cite|improve this answer









              $endgroup$


















                1












                $begingroup$

                Let B(n) be the balance at the end of n months.

                B(0) = a = 160,000.

                B(n + 1) = 1.05.B(n) - 1200.



                B(1) is easy to calculate. Calculate B(1) and B(2) to get a sense for B(n) and how complicated it will be. Don't use 160,000, use a to make this clearer.



                All this mortgage stuff is so well known,

                it's on the web, formulas and tables both.






                share|cite|improve this answer









                $endgroup$
















                  1












                  1








                  1





                  $begingroup$

                  Let B(n) be the balance at the end of n months.

                  B(0) = a = 160,000.

                  B(n + 1) = 1.05.B(n) - 1200.



                  B(1) is easy to calculate. Calculate B(1) and B(2) to get a sense for B(n) and how complicated it will be. Don't use 160,000, use a to make this clearer.



                  All this mortgage stuff is so well known,

                  it's on the web, formulas and tables both.






                  share|cite|improve this answer









                  $endgroup$



                  Let B(n) be the balance at the end of n months.

                  B(0) = a = 160,000.

                  B(n + 1) = 1.05.B(n) - 1200.



                  B(1) is easy to calculate. Calculate B(1) and B(2) to get a sense for B(n) and how complicated it will be. Don't use 160,000, use a to make this clearer.



                  All this mortgage stuff is so well known,

                  it's on the web, formulas and tables both.







                  share|cite|improve this answer












                  share|cite|improve this answer



                  share|cite|improve this answer










                  answered Dec 1 '18 at 23:54









                  William ElliotWilliam Elliot

                  7,4062720




                  7,4062720























                      1












                      $begingroup$

                      You're doing fine so far. The next step is to try to write it in symbols instead of numbers, so that you can see the pattern easier.



                      Let $P_n$ be the amount of the loan outstanding after $n$ months. $P_0$is the amount of the loan after $0$ months, that is, at the beginning, so $P_0=160000.$ Now, if we know $P_n,$ how do we calculate $P_{n+1}?$ You already shown how to do it; take $0.5%$ of subtract that from $1200$, and the subtract the difference from $P_n$ $$
                      P_{n+1}=P_n-(1200-.05P_n)=1.05P_n-1200tag{1}$$



                      Now write out he same examples you did, but using symbols this time, by repeated applying equation $(1).$
                      $$begin{align}
                      P_1&=1.005P_0-1200\
                      P_2&=1.005P_1-1200=1.005(1.005P_0-1200)-1200 = 1.005^2P_0-1200(1+1.005)\
                      P_3&=1.005P_2-1200=1.005^3P_0-1200(1+1.005+1.005^2)\
                      &vdots
                      end{align}$$



                      As to what they want you to do, I'm guessing, because I don't know what tools you have available. I would think they want you to use equation $(1)$ to calculate the various values of $P_n$ perhaps using some computer spreadsheet program, and graph the values of $P_n$ over time, to see when the value first becomes negative, so that the loan has been paid off.



                      Then they want you to figure out the general formula for $P_n,$ a try to compute the value of $n$ for which $P_n$ = $0$. This will almost surely not be a whole number.






                      share|cite|improve this answer









                      $endgroup$


















                        1












                        $begingroup$

                        You're doing fine so far. The next step is to try to write it in symbols instead of numbers, so that you can see the pattern easier.



                        Let $P_n$ be the amount of the loan outstanding after $n$ months. $P_0$is the amount of the loan after $0$ months, that is, at the beginning, so $P_0=160000.$ Now, if we know $P_n,$ how do we calculate $P_{n+1}?$ You already shown how to do it; take $0.5%$ of subtract that from $1200$, and the subtract the difference from $P_n$ $$
                        P_{n+1}=P_n-(1200-.05P_n)=1.05P_n-1200tag{1}$$



                        Now write out he same examples you did, but using symbols this time, by repeated applying equation $(1).$
                        $$begin{align}
                        P_1&=1.005P_0-1200\
                        P_2&=1.005P_1-1200=1.005(1.005P_0-1200)-1200 = 1.005^2P_0-1200(1+1.005)\
                        P_3&=1.005P_2-1200=1.005^3P_0-1200(1+1.005+1.005^2)\
                        &vdots
                        end{align}$$



                        As to what they want you to do, I'm guessing, because I don't know what tools you have available. I would think they want you to use equation $(1)$ to calculate the various values of $P_n$ perhaps using some computer spreadsheet program, and graph the values of $P_n$ over time, to see when the value first becomes negative, so that the loan has been paid off.



                        Then they want you to figure out the general formula for $P_n,$ a try to compute the value of $n$ for which $P_n$ = $0$. This will almost surely not be a whole number.






                        share|cite|improve this answer









                        $endgroup$
















                          1












                          1








                          1





                          $begingroup$

                          You're doing fine so far. The next step is to try to write it in symbols instead of numbers, so that you can see the pattern easier.



                          Let $P_n$ be the amount of the loan outstanding after $n$ months. $P_0$is the amount of the loan after $0$ months, that is, at the beginning, so $P_0=160000.$ Now, if we know $P_n,$ how do we calculate $P_{n+1}?$ You already shown how to do it; take $0.5%$ of subtract that from $1200$, and the subtract the difference from $P_n$ $$
                          P_{n+1}=P_n-(1200-.05P_n)=1.05P_n-1200tag{1}$$



                          Now write out he same examples you did, but using symbols this time, by repeated applying equation $(1).$
                          $$begin{align}
                          P_1&=1.005P_0-1200\
                          P_2&=1.005P_1-1200=1.005(1.005P_0-1200)-1200 = 1.005^2P_0-1200(1+1.005)\
                          P_3&=1.005P_2-1200=1.005^3P_0-1200(1+1.005+1.005^2)\
                          &vdots
                          end{align}$$



                          As to what they want you to do, I'm guessing, because I don't know what tools you have available. I would think they want you to use equation $(1)$ to calculate the various values of $P_n$ perhaps using some computer spreadsheet program, and graph the values of $P_n$ over time, to see when the value first becomes negative, so that the loan has been paid off.



                          Then they want you to figure out the general formula for $P_n,$ a try to compute the value of $n$ for which $P_n$ = $0$. This will almost surely not be a whole number.






                          share|cite|improve this answer









                          $endgroup$



                          You're doing fine so far. The next step is to try to write it in symbols instead of numbers, so that you can see the pattern easier.



                          Let $P_n$ be the amount of the loan outstanding after $n$ months. $P_0$is the amount of the loan after $0$ months, that is, at the beginning, so $P_0=160000.$ Now, if we know $P_n,$ how do we calculate $P_{n+1}?$ You already shown how to do it; take $0.5%$ of subtract that from $1200$, and the subtract the difference from $P_n$ $$
                          P_{n+1}=P_n-(1200-.05P_n)=1.05P_n-1200tag{1}$$



                          Now write out he same examples you did, but using symbols this time, by repeated applying equation $(1).$
                          $$begin{align}
                          P_1&=1.005P_0-1200\
                          P_2&=1.005P_1-1200=1.005(1.005P_0-1200)-1200 = 1.005^2P_0-1200(1+1.005)\
                          P_3&=1.005P_2-1200=1.005^3P_0-1200(1+1.005+1.005^2)\
                          &vdots
                          end{align}$$



                          As to what they want you to do, I'm guessing, because I don't know what tools you have available. I would think they want you to use equation $(1)$ to calculate the various values of $P_n$ perhaps using some computer spreadsheet program, and graph the values of $P_n$ over time, to see when the value first becomes negative, so that the loan has been paid off.



                          Then they want you to figure out the general formula for $P_n,$ a try to compute the value of $n$ for which $P_n$ = $0$. This will almost surely not be a whole number.







                          share|cite|improve this answer












                          share|cite|improve this answer



                          share|cite|improve this answer










                          answered Dec 2 '18 at 0:13









                          saulspatzsaulspatz

                          14.1k21329




                          14.1k21329






























                              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%2f3021974%2fsuppose-you-take-out-a-home-mortgage-for-160000-at-a-monthly-interest-rate-of%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

                              Index of /

                              Tribalistas

                              Listed building