Another Math Problem

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  • Stuart 0366
    Top Poster +
    • Sep 2009
    • 206

    #1

    Another Math Problem

    How can 3+4x5=23?
    My boy has been told that is the answer to this sum...he is in 3rd year at college.
    My response, (as was his) is the only way this would work is if the sum is written 3+(4x5)=23
    Are we right?
    Virgin Tivo 500Gb
  • thewizardofodds
    DK Veteran
    • Nov 2008
    • 924

    #2
    i agree with you

    Comment

    • larryoke
      DK Veteran
      • Feb 2009
      • 404

      #3
      Originally posted by Stuart 0366
      How can 3+4x5=23?
      My boy has been told that is the answer to this sum...he is in 3rd year at college.
      My response, (as was his) is the only way this would work is if the sum is written 3+(4x5)=23
      Are we right?
      I think I would tell your son to stuff a calculator up his tutor's a**e 3+4x5=35, No maths genius but I would go with your calculation then apply for the tutor's job.

      Comment

      • masur123
        DK Veteran
        • Aug 2009
        • 674

        #4
        Depends if this formula is being used in an excel spreadsheet. Try it... if you do =3+4*5 it will show 23, if you do =3+(4*5) it will also show 23, if you do =(3+4)*5 you will get 35.

        However if you do 3+4*5 on a calculator it will show 35. I guess the calculator will do the sum in order of the sum, whilst excel doesnt.....

        Guess its just the way microsoft have worked it out for excel

        Comment

        • cgscott
          V.I.P. Member
          • Jul 2008
          • 3513

          #5
          If x=3 and y=5 and b=4

          then x+(y*b)=23 or as you mentioned above. Obviously the tutor forgot to put the brackets in. Simple mistake. I wouldve laughed at him.
          sigpic


          Patience is a virtue.

          Comment

          • pawliukazz
            DK Veteran
            • Nov 2009
            • 530

            #6
            Originally posted by Stuart 0366
            How can 3+4x5=23?
            My boy has been told that is the answer to this sum...he is in 3rd year at college.
            My response, (as was his) is the only way this would work is if the sum is written 3+(4x5)=23
            Are we right?
            You are both right:

            3+4x5=23
            3+(4x5)=23

            See, the point is that multiplying and dividing goes in the first place (in the first place of all actions in math i mean plus, or minus).

            Sorry if it was hard to understand me, but the point is that your both answers are right
            Last edited by pawliukazz; 25 August, 2010, 18:42.
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            Comment

            • pawliukazz
              DK Veteran
              • Nov 2009
              • 530

              #7
              Obviously i can laugh from most of you here, because you don't know math's basics....

              @larryoke you can shut your math to your's *** because your answer was dummest of all...
              Remote support for advanced Car & ATV dump mods
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              • chucklor
                DK Veteran
                • Jun 2009
                • 470

                #8
                4x5+3=23
                3+4x5=35
                And as you say 3+(4+5)=23

                Tell your son to change lecturers, basic maths, same as change the side change the sign, work from left to right unless brackets are in the equation, god help him if they get on calculus or differentiation.......

                Comment

                • rogermcgomry
                  Junior Member
                  • Feb 2010
                  • 30

                  #9
                  The answer is 23 unless parentheses surround the addition.
                  P Parentheses first
                  E Exponents (ie Powers and Square Roots, etc.)
                  MD Multiplication and Division (left-to-right)
                  AS Addition and Subtraction (left-to-right)

                  Order of operations - Wikipedia, the free encyclopedia

                  Comment

                  • pawliukazz
                    DK Veteran
                    • Nov 2009
                    • 530

                    #10
                    Guys, stop posting bad answers, the answers are the same

                    3+4*5=23
                    3+(4*5)=23


                    Please trust me, they are the same!

                    rogermcgomry is right
                    Remote support for advanced Car & ATV dump mods
                    Volvo config mods, dump repairs (CEM, ECU, SRS, ICM, DIM)
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                    Comment

                    • Stuart 0366
                      Top Poster +
                      • Sep 2009
                      • 206

                      #11
                      If both answers come up as the same then why are we teaching our primary school children wrong formulae. I was taught from left to right unless brackets are in the mix?
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                      Comment

                      • Mjolinor
                        V.I.P. VIC
                        • Jan 2009
                        • 1093

                        #12
                        B brackets
                        O of
                        D division
                        M multiplication
                        A addition
                        S subtraction

                        You lot never heard of that. It is the most basic rule of arithmetic.

                        Comment

                        • chucklor
                          DK Veteran
                          • Jun 2009
                          • 470

                          #13
                          I have just typed in 3+4x5 into my calculator and the answer came back as 35..
                          However when I put it into this its a different storyBasic Calculator

                          Comment

                          • thered
                            V.I.P. Member
                            • Aug 2008
                            • 4915

                            #14
                            Originally posted by Stuart 0366
                            If both answers come up as the same then why are we teaching our primary school children wrong formulae. I was taught from left to right unless brackets are in the mix?
                            same as me left to right unless brackets are used then its brackets first as a sum its 35

                            to get 23 you need to use brackets

                            or does the calculator lie

                            Comment

                            • Stuart 0366
                              Top Poster +
                              • Sep 2009
                              • 206

                              #15
                              Originally posted by Mjolinor
                              B brackets
                              O of
                              D division
                              M multiplication
                              A addition
                              S subtraction

                              You lot never heard of that. It is the most basic rule of arithmetic.

                              Heard of it yes, but not taught at primary school level mate, where it should be.
                              Virgin Tivo 500Gb

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