What is the difference between simple interest and simple discounting?












1












$begingroup$


I have been given the following statements:



"Simple interest: $C$ now $equiv (1+in)C$ in $n$ years; $C$ in $n$ years $equiv frac{C}{1+in}$ now.



Simple discounting:
$C$ in $n$ years $equiv (1−dn)C$ now; $C$ now $equiv frac{C}{1-dn}$ in $n$ years.



Where $d=frac{i}{1+i}$"



These statements imply that simple interest and simple discounting are not equivalent, since the statements do not equate to one another. Why is this, and what is the difference between simple interest and simple discounting?



Thanks










share|cite|improve this question









$endgroup$

















    1












    $begingroup$


    I have been given the following statements:



    "Simple interest: $C$ now $equiv (1+in)C$ in $n$ years; $C$ in $n$ years $equiv frac{C}{1+in}$ now.



    Simple discounting:
    $C$ in $n$ years $equiv (1−dn)C$ now; $C$ now $equiv frac{C}{1-dn}$ in $n$ years.



    Where $d=frac{i}{1+i}$"



    These statements imply that simple interest and simple discounting are not equivalent, since the statements do not equate to one another. Why is this, and what is the difference between simple interest and simple discounting?



    Thanks










    share|cite|improve this question









    $endgroup$















      1












      1








      1





      $begingroup$


      I have been given the following statements:



      "Simple interest: $C$ now $equiv (1+in)C$ in $n$ years; $C$ in $n$ years $equiv frac{C}{1+in}$ now.



      Simple discounting:
      $C$ in $n$ years $equiv (1−dn)C$ now; $C$ now $equiv frac{C}{1-dn}$ in $n$ years.



      Where $d=frac{i}{1+i}$"



      These statements imply that simple interest and simple discounting are not equivalent, since the statements do not equate to one another. Why is this, and what is the difference between simple interest and simple discounting?



      Thanks










      share|cite|improve this question









      $endgroup$




      I have been given the following statements:



      "Simple interest: $C$ now $equiv (1+in)C$ in $n$ years; $C$ in $n$ years $equiv frac{C}{1+in}$ now.



      Simple discounting:
      $C$ in $n$ years $equiv (1−dn)C$ now; $C$ now $equiv frac{C}{1-dn}$ in $n$ years.



      Where $d=frac{i}{1+i}$"



      These statements imply that simple interest and simple discounting are not equivalent, since the statements do not equate to one another. Why is this, and what is the difference between simple interest and simple discounting?



      Thanks







      finance






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked May 18 '15 at 9:48









      M SmithM Smith

      1,216823




      1,216823






















          1 Answer
          1






          active

          oldest

          votes


















          0












          $begingroup$

          I think you have the wrong formula for d.



          $C_{0c}$: present value (simple compound)



          $C_{0d}$: present value (simple discount)



          $C_{nd}$: future value (simple discount)



          $C_{nc}$: future value (simple compound)



          $C_{nc}=C_{0c}cdot (1+in)$



          $C_{0d}=C_{nd}cdot frac{1}{1-dcdot n}=C_{nd}cdot frac{1}{1-frac{icdot n}{1+icdot n}}$



          with $boxed{d=frac{i}{1+icdot n}}$



          Here I have a different expression for d.



          The future value of the simple compound has to be equal to the present value of the simple discount. This is your asked connection.



          $C_{0c}cdot (1+in)=C_{nd}cdot frac{1}{1-frac{icdot n}{1+icdot n}}$



          $C_{0c}$ and $C_{nd}$ can be cancelled, because they are equal, too.



          $(1+in)= frac{1}{1-frac{icdot n}{1+icdot n}}$



          Multiplying the equation by the denominator of the RHS.



          $(1+in)cdot left( 1-frac{icdot n}{1+icdot n} right)=1$



          Now you can proof, if the equation is true.






          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%2f1287658%2fwhat-is-the-difference-between-simple-interest-and-simple-discounting%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









            0












            $begingroup$

            I think you have the wrong formula for d.



            $C_{0c}$: present value (simple compound)



            $C_{0d}$: present value (simple discount)



            $C_{nd}$: future value (simple discount)



            $C_{nc}$: future value (simple compound)



            $C_{nc}=C_{0c}cdot (1+in)$



            $C_{0d}=C_{nd}cdot frac{1}{1-dcdot n}=C_{nd}cdot frac{1}{1-frac{icdot n}{1+icdot n}}$



            with $boxed{d=frac{i}{1+icdot n}}$



            Here I have a different expression for d.



            The future value of the simple compound has to be equal to the present value of the simple discount. This is your asked connection.



            $C_{0c}cdot (1+in)=C_{nd}cdot frac{1}{1-frac{icdot n}{1+icdot n}}$



            $C_{0c}$ and $C_{nd}$ can be cancelled, because they are equal, too.



            $(1+in)= frac{1}{1-frac{icdot n}{1+icdot n}}$



            Multiplying the equation by the denominator of the RHS.



            $(1+in)cdot left( 1-frac{icdot n}{1+icdot n} right)=1$



            Now you can proof, if the equation is true.






            share|cite|improve this answer











            $endgroup$


















              0












              $begingroup$

              I think you have the wrong formula for d.



              $C_{0c}$: present value (simple compound)



              $C_{0d}$: present value (simple discount)



              $C_{nd}$: future value (simple discount)



              $C_{nc}$: future value (simple compound)



              $C_{nc}=C_{0c}cdot (1+in)$



              $C_{0d}=C_{nd}cdot frac{1}{1-dcdot n}=C_{nd}cdot frac{1}{1-frac{icdot n}{1+icdot n}}$



              with $boxed{d=frac{i}{1+icdot n}}$



              Here I have a different expression for d.



              The future value of the simple compound has to be equal to the present value of the simple discount. This is your asked connection.



              $C_{0c}cdot (1+in)=C_{nd}cdot frac{1}{1-frac{icdot n}{1+icdot n}}$



              $C_{0c}$ and $C_{nd}$ can be cancelled, because they are equal, too.



              $(1+in)= frac{1}{1-frac{icdot n}{1+icdot n}}$



              Multiplying the equation by the denominator of the RHS.



              $(1+in)cdot left( 1-frac{icdot n}{1+icdot n} right)=1$



              Now you can proof, if the equation is true.






              share|cite|improve this answer











              $endgroup$
















                0












                0








                0





                $begingroup$

                I think you have the wrong formula for d.



                $C_{0c}$: present value (simple compound)



                $C_{0d}$: present value (simple discount)



                $C_{nd}$: future value (simple discount)



                $C_{nc}$: future value (simple compound)



                $C_{nc}=C_{0c}cdot (1+in)$



                $C_{0d}=C_{nd}cdot frac{1}{1-dcdot n}=C_{nd}cdot frac{1}{1-frac{icdot n}{1+icdot n}}$



                with $boxed{d=frac{i}{1+icdot n}}$



                Here I have a different expression for d.



                The future value of the simple compound has to be equal to the present value of the simple discount. This is your asked connection.



                $C_{0c}cdot (1+in)=C_{nd}cdot frac{1}{1-frac{icdot n}{1+icdot n}}$



                $C_{0c}$ and $C_{nd}$ can be cancelled, because they are equal, too.



                $(1+in)= frac{1}{1-frac{icdot n}{1+icdot n}}$



                Multiplying the equation by the denominator of the RHS.



                $(1+in)cdot left( 1-frac{icdot n}{1+icdot n} right)=1$



                Now you can proof, if the equation is true.






                share|cite|improve this answer











                $endgroup$



                I think you have the wrong formula for d.



                $C_{0c}$: present value (simple compound)



                $C_{0d}$: present value (simple discount)



                $C_{nd}$: future value (simple discount)



                $C_{nc}$: future value (simple compound)



                $C_{nc}=C_{0c}cdot (1+in)$



                $C_{0d}=C_{nd}cdot frac{1}{1-dcdot n}=C_{nd}cdot frac{1}{1-frac{icdot n}{1+icdot n}}$



                with $boxed{d=frac{i}{1+icdot n}}$



                Here I have a different expression for d.



                The future value of the simple compound has to be equal to the present value of the simple discount. This is your asked connection.



                $C_{0c}cdot (1+in)=C_{nd}cdot frac{1}{1-frac{icdot n}{1+icdot n}}$



                $C_{0c}$ and $C_{nd}$ can be cancelled, because they are equal, too.



                $(1+in)= frac{1}{1-frac{icdot n}{1+icdot n}}$



                Multiplying the equation by the denominator of the RHS.



                $(1+in)cdot left( 1-frac{icdot n}{1+icdot n} right)=1$



                Now you can proof, if the equation is true.







                share|cite|improve this answer














                share|cite|improve this answer



                share|cite|improve this answer








                edited May 18 '15 at 23:57

























                answered May 18 '15 at 23:25









                callculuscallculus

                18.7k31428




                18.7k31428






























                    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%2f1287658%2fwhat-is-the-difference-between-simple-interest-and-simple-discounting%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

                    How do I know what Microsoft account the skydrive app is syncing to?

                    When does type information flow backwards in C++?

                    Grease: Live!