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Math quiz [solved]

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  • M Mustafa Ismail Mustafa

    OK, let's see if you guys can work this one out :) The numbers: 1, 2, 3, 4, 5 and the operations +, -, *, / can be used in any order (parenthesis are free to control the order of evaluation) All the preceding mentioned numbers and operations can be used in any order once and only once to provide the result of 28. Remember, each of the operations can be used once only and each of the numbers can be used once only. You have to use them all to achieve your goal. You may begin :) [solution] Credited to aspdotnetdev (4 - (1/2)) * (5 + 3) = 28. Points awarded. Would you like me to make this a feature? Sorta like the CCC but for us more Mathematically as opposed to being "constantly high on peyote in order to be able to answer the CCC"?

    If the post was helpful, please vote, eh! Current activities: Playing Star Craft II. Don't bother me, eh? Now and forever, defiant to the end. What is Multiple Sclerosis[^]?

    modified on Friday, October 15, 2010 2:52 PM

    L Offline
    L Offline
    leppie
    wrote on last edited by
    #7

    ((1 + 3) * 2) + (4 * 5)

    Took 4 seconds. How I got there: Started with biggest number first.

    xacc.ide
    IronScheme - 1.0 RC 1 - out now!
    ((λ (x) `(,x ',x)) '(λ (x) `(,x ',x))) The Scheme Programming Language – Fourth Edition

    S 1 Reply Last reply
    0
    • L leppie

      ((1 + 3) * 2) + (4 * 5)

      Took 4 seconds. How I got there: Started with biggest number first.

      xacc.ide
      IronScheme - 1.0 RC 1 - out now!
      ((λ (x) `(,x ',x)) '(λ (x) `(,x ',x))) The Scheme Programming Language – Fourth Edition

      S Offline
      S Offline
      SinghUlarity
      wrote on last edited by
      #8

      To be wrong :-D

      I are n00b.

      L 1 Reply Last reply
      0
      • S SinghUlarity

        To be wrong :-D

        I are n00b.

        L Offline
        L Offline
        leppie
        wrote on last edited by
        #9

        SinghUlarity... wrote:

        To be wrong

        FFS, I missed reading one word! :doh: Damnit, now it is a lot harder!

        xacc.ide
        IronScheme - 1.0 RC 1 - out now!
        ((λ (x) `(,x ',x)) '(λ (x) `(,x ',x))) The Scheme Programming Language – Fourth Edition

        S 1 Reply Last reply
        0
        • M Mustafa Ismail Mustafa

          OK, let's see if you guys can work this one out :) The numbers: 1, 2, 3, 4, 5 and the operations +, -, *, / can be used in any order (parenthesis are free to control the order of evaluation) All the preceding mentioned numbers and operations can be used in any order once and only once to provide the result of 28. Remember, each of the operations can be used once only and each of the numbers can be used once only. You have to use them all to achieve your goal. You may begin :) [solution] Credited to aspdotnetdev (4 - (1/2)) * (5 + 3) = 28. Points awarded. Would you like me to make this a feature? Sorta like the CCC but for us more Mathematically as opposed to being "constantly high on peyote in order to be able to answer the CCC"?

          If the post was helpful, please vote, eh! Current activities: Playing Star Craft II. Don't bother me, eh? Now and forever, defiant to the end. What is Multiple Sclerosis[^]?

          modified on Friday, October 15, 2010 2:52 PM

          A Offline
          A Offline
          AspDotNetDev
          wrote on last edited by
          #10

          4 * (5 + 2)

          [Forum Guidelines]

          L S 2 Replies Last reply
          0
          • A AspDotNetDev

            4 * (5 + 2)

            [Forum Guidelines]

            L Offline
            L Offline
            leppie
            wrote on last edited by
            #11

            Very sneaky! Finding the loophole. The OP should have used must instead of can :)

            xacc.ide
            IronScheme - 1.0 RC 1 - out now!
            ((λ (x) `(,x ',x)) '(λ (x) `(,x ',x))) The Scheme Programming Language – Fourth Edition

            A H 2 Replies Last reply
            0
            • C Chris Meech

              (2+3)*5+4-1 = 28. My kids and I used to play this game all the time. :) [EDIT] Just saw your rule about using all operators and only once. Not familiar with that one. :doh: :doh: :doh:

              Chris Meech I am Canadian. [heard in a local bar] In theory there is no difference between theory and practice. In practice there is. [Yogi Berra]

              A Offline
              A Offline
              AspDotNetDev
              wrote on last edited by
              #12

              Hint: 4 * 7 = 28 :)

              [Forum Guidelines]

              1 Reply Last reply
              0
              • L leppie

                SinghUlarity... wrote:

                To be wrong

                FFS, I missed reading one word! :doh: Damnit, now it is a lot harder!

                xacc.ide
                IronScheme - 1.0 RC 1 - out now!
                ((λ (x) `(,x ',x)) '(λ (x) `(,x ',x))) The Scheme Programming Language – Fourth Edition

                S Offline
                S Offline
                SinghUlarity
                wrote on last edited by
                #13

                And that's how the clients end up with a Monkey when they order a Giraffe :laugh:

                I are n00b.

                1 Reply Last reply
                0
                • L leppie

                  Very sneaky! Finding the loophole. The OP should have used must instead of can :)

                  xacc.ide
                  IronScheme - 1.0 RC 1 - out now!
                  ((λ (x) `(,x ',x)) '(λ (x) `(,x ',x))) The Scheme Programming Language – Fourth Edition

                  A Offline
                  A Offline
                  AspDotNetDev
                  wrote on last edited by
                  #14

                  Just saw this bit: "You have to use them all to achieve your goal." :((

                  [Forum Guidelines]

                  1 Reply Last reply
                  0
                  • A AspDotNetDev

                    4 * (5 + 2)

                    [Forum Guidelines]

                    S Offline
                    S Offline
                    SinghUlarity
                    wrote on last edited by
                    #15

                    You have to use them all to achieve your goal. :rolleyes:

                    I are n00b.

                    1 Reply Last reply
                    0
                    • L leppie

                      Very sneaky! Finding the loophole. The OP should have used must instead of can :)

                      xacc.ide
                      IronScheme - 1.0 RC 1 - out now!
                      ((λ (x) `(,x ',x)) '(λ (x) `(,x ',x))) The Scheme Programming Language – Fourth Edition

                      H Offline
                      H Offline
                      Henry Minute
                      wrote on last edited by
                      #16

                      Mustafa did say "You have to use them all". Last sentence.

                      Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”

                      A 1 Reply Last reply
                      0
                      • H Henry Minute

                        Mustafa did say "You have to use them all". Last sentence.

                        Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”

                        A Offline
                        A Offline
                        AspDotNetDev
                        wrote on last edited by
                        #17

                        Perhaps the OP was mistaken. ;P

                        [Forum Guidelines]

                        M 1 Reply Last reply
                        0
                        • A AspDotNetDev

                          Perhaps the OP was mistaken. ;P

                          [Forum Guidelines]

                          M Offline
                          M Offline
                          Mustafa Ismail Mustafa
                          wrote on last edited by
                          #18

                          Nope, not mistaken :)

                          If the post was helpful, please vote, eh! Current activities: Playing Star Craft II. Don't bother me, eh? Now and forever, defiant to the end. What is Multiple Sclerosis[^]?

                          1 Reply Last reply
                          0
                          • M Mustafa Ismail Mustafa

                            OK, let's see if you guys can work this one out :) The numbers: 1, 2, 3, 4, 5 and the operations +, -, *, / can be used in any order (parenthesis are free to control the order of evaluation) All the preceding mentioned numbers and operations can be used in any order once and only once to provide the result of 28. Remember, each of the operations can be used once only and each of the numbers can be used once only. You have to use them all to achieve your goal. You may begin :) [solution] Credited to aspdotnetdev (4 - (1/2)) * (5 + 3) = 28. Points awarded. Would you like me to make this a feature? Sorta like the CCC but for us more Mathematically as opposed to being "constantly high on peyote in order to be able to answer the CCC"?

                            If the post was helpful, please vote, eh! Current activities: Playing Star Craft II. Don't bother me, eh? Now and forever, defiant to the end. What is Multiple Sclerosis[^]?

                            modified on Friday, October 15, 2010 2:52 PM

                            A Offline
                            A Offline
                            AspDotNetDev
                            wrote on last edited by
                            #19

                            I do not think a solution exists. The closest my computer could get was 27. :((

                            using System.Collections.Generic;
                            using System.Windows.Forms;

                            namespace WindowsFormsApplication1
                            {
                            public partial class Form1 : Form
                            {

                                delegate double Op(double num1, double num2);
                            
                                public Form1()
                                {
                                    InitializeComponent();
                            
                                    List<Op> ops = new List<Op> { new Op(M), new Op(D), new Op(A), new Op(S) };
                            
                                    List<int> opOrder = new List<int> { 0, 0, 0, 0 };
                            
                                    List<double> results = new List<double>();
                                    for (int op1 = 0; op1 < 4; op1++)
                                    {
                                        for (int op2 = 0; op2 < 4; op2++)
                                        {
                                            for (int op3 = 0; op3 < 4; op3++)
                                            {
                                                for (int op4 = 0; op4 < 4; op4++)
                                                {
                                                    for (int n1 = 1; n1 <= 5; n1++)
                                                    {
                                                        for (int n2 = 1; n2 <= 5; n2++)
                                                        {
                                                            for (int n3 = 1; n3 <= 5; n3++)
                                                            {
                                                                for (int n4 = 1; n4 <= 5; n4++)
                                                                {
                                                                    for (int n5 = 1; n5 <= 5; n5++)
                                                                    {
                                                                        bool valid = true;
                                                                        List<int> opTest = new List<int> { op1, op2, op3, op4 };
                                                                        List<int> numTest = new List<int> { n1, n2, n3, n4, n5 };
                                                                        for (int i = 0; i < 4; i++)
                                                                        {
                                                                            for (int j = 0; j < 4; j++)
                                                                            {
                                                                                if (i != j)
                                                                                {
                                                                                    if (opTest\[i\] == opTest\[j\])
                                                                                    {
                                                                                        valid = false;
                                                                                    }
                                                                                }
                            
                            I S 2 Replies Last reply
                            0
                            • A AspDotNetDev

                              I do not think a solution exists. The closest my computer could get was 27. :((

                              using System.Collections.Generic;
                              using System.Windows.Forms;

                              namespace WindowsFormsApplication1
                              {
                              public partial class Form1 : Form
                              {

                                  delegate double Op(double num1, double num2);
                              
                                  public Form1()
                                  {
                                      InitializeComponent();
                              
                                      List<Op> ops = new List<Op> { new Op(M), new Op(D), new Op(A), new Op(S) };
                              
                                      List<int> opOrder = new List<int> { 0, 0, 0, 0 };
                              
                                      List<double> results = new List<double>();
                                      for (int op1 = 0; op1 < 4; op1++)
                                      {
                                          for (int op2 = 0; op2 < 4; op2++)
                                          {
                                              for (int op3 = 0; op3 < 4; op3++)
                                              {
                                                  for (int op4 = 0; op4 < 4; op4++)
                                                  {
                                                      for (int n1 = 1; n1 <= 5; n1++)
                                                      {
                                                          for (int n2 = 1; n2 <= 5; n2++)
                                                          {
                                                              for (int n3 = 1; n3 <= 5; n3++)
                                                              {
                                                                  for (int n4 = 1; n4 <= 5; n4++)
                                                                  {
                                                                      for (int n5 = 1; n5 <= 5; n5++)
                                                                      {
                                                                          bool valid = true;
                                                                          List<int> opTest = new List<int> { op1, op2, op3, op4 };
                                                                          List<int> numTest = new List<int> { n1, n2, n3, n4, n5 };
                                                                          for (int i = 0; i < 4; i++)
                                                                          {
                                                                              for (int j = 0; j < 4; j++)
                                                                              {
                                                                                  if (i != j)
                                                                                  {
                                                                                      if (opTest\[i\] == opTest\[j\])
                                                                                      {
                                                                                          valid = false;
                                                                                      }
                                                                                  }
                              
                              I Offline
                              I Offline
                              Ian Shlasko
                              wrote on last edited by
                              #20

                              static void Main(string[] args)
                              {
                              int[] nums = new int[] { 1,1,1,1,1};

                              while (true)
                              {
                                  Signs\[\] signs = new Signs\[4\];
                              
                                  while (true)
                                  {
                                      if (nums.Sum() == 15)
                                      {
                              
                                          double x = nums\[0\];
                                          for (int idx = 1; idx < 5; idx++)
                                              switch (signs\[idx - 1\])
                                              {
                                                  case Signs.Plus: x += nums\[idx\]; break;
                                                  case Signs.Minus: x -= nums\[idx\]; break;
                                                  case Signs.Div: x /= Convert.ToDouble(nums\[idx\]); break;
                                                  case Signs.Times: x \*= nums\[idx\]; break;
                                              }
                              
                                          if (x == 28 && nums.Distinct().Count() != 5 && signs.Distinct().Count() == 4)
                                          {
                                              // Breakpoint here... What?  I'm lazy.
                                          }
                              
                                      }
                              
                                      signs\[3\]++;
                                      for (int idx = 3; idx > 0; idx--)
                                          if ((int)signs\[idx\] == 4)
                                          {
                                              signs\[idx\] = Signs.Plus;
                                              signs\[idx - 1\]++;
                                          }
                                      if ((int)signs\[0\] > 3) break;
                              
                                      Console.Write('.');
                                  }
                              
                              
                              
                                  nums\[4\]++;
                                  for (int idx = 4; idx > 0; idx--)
                                  {
                                      if (nums\[idx\] > 5)
                                      {
                                          nums\[idx\] = 1;
                                          nums\[idx - 1\]++;
                                      }
                                  }
                                  if (nums\[0\] > 5) break;
                              }
                              

                              }

                              private enum Signs : int
                              {
                              Plus = 0,
                              Minus = 1,
                              Times = 2,
                              Div = 3
                              }

                              But this isn't inclusive... It wouldn't try something like (5+1)*(4-3)/2, because you can't do that sequentially.

                              Proud to have finally moved to the A-Ark. Which one are you in?
                              Author of the Guardians Saga (Sci-Fi/Fantasy novels)

                              A 1 Reply Last reply
                              0
                              • I Ian Shlasko

                                static void Main(string[] args)
                                {
                                int[] nums = new int[] { 1,1,1,1,1};

                                while (true)
                                {
                                    Signs\[\] signs = new Signs\[4\];
                                
                                    while (true)
                                    {
                                        if (nums.Sum() == 15)
                                        {
                                
                                            double x = nums\[0\];
                                            for (int idx = 1; idx < 5; idx++)
                                                switch (signs\[idx - 1\])
                                                {
                                                    case Signs.Plus: x += nums\[idx\]; break;
                                                    case Signs.Minus: x -= nums\[idx\]; break;
                                                    case Signs.Div: x /= Convert.ToDouble(nums\[idx\]); break;
                                                    case Signs.Times: x \*= nums\[idx\]; break;
                                                }
                                
                                            if (x == 28 && nums.Distinct().Count() != 5 && signs.Distinct().Count() == 4)
                                            {
                                                // Breakpoint here... What?  I'm lazy.
                                            }
                                
                                        }
                                
                                        signs\[3\]++;
                                        for (int idx = 3; idx > 0; idx--)
                                            if ((int)signs\[idx\] == 4)
                                            {
                                                signs\[idx\] = Signs.Plus;
                                                signs\[idx - 1\]++;
                                            }
                                        if ((int)signs\[0\] > 3) break;
                                
                                        Console.Write('.');
                                    }
                                
                                
                                
                                    nums\[4\]++;
                                    for (int idx = 4; idx > 0; idx--)
                                    {
                                        if (nums\[idx\] > 5)
                                        {
                                            nums\[idx\] = 1;
                                            nums\[idx - 1\]++;
                                        }
                                    }
                                    if (nums\[0\] > 5) break;
                                }
                                

                                }

                                private enum Signs : int
                                {
                                Plus = 0,
                                Minus = 1,
                                Times = 2,
                                Div = 3
                                }

                                But this isn't inclusive... It wouldn't try something like (5+1)*(4-3)/2, because you can't do that sequentially.

                                Proud to have finally moved to the A-Ark. Which one are you in?
                                Author of the Guardians Saga (Sci-Fi/Fantasy novels)

                                A Offline
                                A Offline
                                AspDotNetDev
                                wrote on last edited by
                                #21

                                Dang, I think you're right. I didn't account for parens. Will attempt to modify...

                                [Forum Guidelines]

                                1 Reply Last reply
                                0
                                • A AspDotNetDev

                                  I do not think a solution exists. The closest my computer could get was 27. :((

                                  using System.Collections.Generic;
                                  using System.Windows.Forms;

                                  namespace WindowsFormsApplication1
                                  {
                                  public partial class Form1 : Form
                                  {

                                      delegate double Op(double num1, double num2);
                                  
                                      public Form1()
                                      {
                                          InitializeComponent();
                                  
                                          List<Op> ops = new List<Op> { new Op(M), new Op(D), new Op(A), new Op(S) };
                                  
                                          List<int> opOrder = new List<int> { 0, 0, 0, 0 };
                                  
                                          List<double> results = new List<double>();
                                          for (int op1 = 0; op1 < 4; op1++)
                                          {
                                              for (int op2 = 0; op2 < 4; op2++)
                                              {
                                                  for (int op3 = 0; op3 < 4; op3++)
                                                  {
                                                      for (int op4 = 0; op4 < 4; op4++)
                                                      {
                                                          for (int n1 = 1; n1 <= 5; n1++)
                                                          {
                                                              for (int n2 = 1; n2 <= 5; n2++)
                                                              {
                                                                  for (int n3 = 1; n3 <= 5; n3++)
                                                                  {
                                                                      for (int n4 = 1; n4 <= 5; n4++)
                                                                      {
                                                                          for (int n5 = 1; n5 <= 5; n5++)
                                                                          {
                                                                              bool valid = true;
                                                                              List<int> opTest = new List<int> { op1, op2, op3, op4 };
                                                                              List<int> numTest = new List<int> { n1, n2, n3, n4, n5 };
                                                                              for (int i = 0; i < 4; i++)
                                                                              {
                                                                                  for (int j = 0; j < 4; j++)
                                                                                  {
                                                                                      if (i != j)
                                                                                      {
                                                                                          if (opTest\[i\] == opTest\[j\])
                                                                                          {
                                                                                              valid = false;
                                                                                          }
                                                                                      }
                                  
                                  S Offline
                                  S Offline
                                  SinghUlarity
                                  wrote on last edited by
                                  #22

                                  While we kill ourselves over this problem, Mustafa is out somewhere enjoying his weekend. This is all a set-up :suss:

                                  I are n00b.

                                  M 1 Reply Last reply
                                  0
                                  • M Mustafa Ismail Mustafa

                                    OK, let's see if you guys can work this one out :) The numbers: 1, 2, 3, 4, 5 and the operations +, -, *, / can be used in any order (parenthesis are free to control the order of evaluation) All the preceding mentioned numbers and operations can be used in any order once and only once to provide the result of 28. Remember, each of the operations can be used once only and each of the numbers can be used once only. You have to use them all to achieve your goal. You may begin :) [solution] Credited to aspdotnetdev (4 - (1/2)) * (5 + 3) = 28. Points awarded. Would you like me to make this a feature? Sorta like the CCC but for us more Mathematically as opposed to being "constantly high on peyote in order to be able to answer the CCC"?

                                    If the post was helpful, please vote, eh! Current activities: Playing Star Craft II. Don't bother me, eh? Now and forever, defiant to the end. What is Multiple Sclerosis[^]?

                                    modified on Friday, October 15, 2010 2:52 PM

                                    G Offline
                                    G Offline
                                    GrumbleDuke
                                    wrote on last edited by
                                    #23

                                    Using integer math: 4*(5+2)-1/3 = 28

                                    I 1 Reply Last reply
                                    0
                                    • G GrumbleDuke

                                      Using integer math: 4*(5+2)-1/3 = 28

                                      I Offline
                                      I Offline
                                      Ian Shlasko
                                      wrote on last edited by
                                      #24

                                      But he said numbers, not integers, so you can't just round it :)

                                      Proud to have finally moved to the A-Ark. Which one are you in?
                                      Author of the Guardians Saga (Sci-Fi/Fantasy novels)

                                      1 Reply Last reply
                                      0
                                      • M Mustafa Ismail Mustafa

                                        OK, let's see if you guys can work this one out :) The numbers: 1, 2, 3, 4, 5 and the operations +, -, *, / can be used in any order (parenthesis are free to control the order of evaluation) All the preceding mentioned numbers and operations can be used in any order once and only once to provide the result of 28. Remember, each of the operations can be used once only and each of the numbers can be used once only. You have to use them all to achieve your goal. You may begin :) [solution] Credited to aspdotnetdev (4 - (1/2)) * (5 + 3) = 28. Points awarded. Would you like me to make this a feature? Sorta like the CCC but for us more Mathematically as opposed to being "constantly high on peyote in order to be able to answer the CCC"?

                                        If the post was helpful, please vote, eh! Current activities: Playing Star Craft II. Don't bother me, eh? Now and forever, defiant to the end. What is Multiple Sclerosis[^]?

                                        modified on Friday, October 15, 2010 2:52 PM

                                        L Offline
                                        L Offline
                                        leppie
                                        wrote on last edited by
                                        #25

                                        or I downvote you! ;P This is not possible I think. I have run an exhaustive search over my brain, and now I am tired.

                                        xacc.ide
                                        IronScheme - 1.0 RC 1 - out now!
                                        ((λ (x) `(,x ',x)) '(λ (x) `(,x ',x))) The Scheme Programming Language – Fourth Edition

                                        A 1 Reply Last reply
                                        0
                                        • L leppie

                                          or I downvote you! ;P This is not possible I think. I have run an exhaustive search over my brain, and now I am tired.

                                          xacc.ide
                                          IronScheme - 1.0 RC 1 - out now!
                                          ((λ (x) `(,x ',x)) '(λ (x) `(,x ',x))) The Scheme Programming Language – Fourth Edition

                                          A Offline
                                          A Offline
                                          AspDotNetDev
                                          wrote on last edited by
                                          #26

                                          If there is a solution, I must find it. If there is not, I must prove that!

                                          [Forum Guidelines]

                                          L 1 Reply Last reply
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