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Another Math Problem

  • 20-10-2010 10:35pm
    #1
    Registered Users, Registered Users 2 Posts: 241 ✭✭


    Brains of AH.... assistance is required.

    Brucy bonus point to the person who can explain the answer in simple terms.

    I had great success in the last one I posted.

    Thanks in Advance

    The letters A,B,C and D each stand for a different Single Digit. Use the clues below to find the digit. Use the clues to find the digits.

    Clues

    • C is greater than 1.
    • C is an odd number.
    • B and D are even Numbers.

    • CA + CB=DC

    What number does D Stand for?


Comments

  • Registered Users, Registered Users 2 Posts: 2,326 ✭✭✭Scuid Mhór


    does that mean we can deduce a is also an odd number?


  • Registered Users, Registered Users 2 Posts: 1,112 ✭✭✭flyton5


    Could you not google it? Or copy it from someone in school tomorrow?


  • Registered Users, Registered Users 2 Posts: 2,326 ✭✭✭Scuid Mhór


    flyton5 wrote: »
    Could you not google it? Or copy it from someone in school tomorrow?

    there is no fun in that, flyton5. to make the after hours crew, you gotta be able to conquer every challenge presented to you. i advise you start trying to solve it instead of sitting on your moral pedestal.


  • Closed Accounts Posts: 1,053 ✭✭✭PanchoVilla


    Brains of AH.... assistance is required.

    Brucy bonus point to the person who can explain the answer in simple terms.

    I had great success in the last one I posted.

    Thanks in Advance

    The letters A,B,C and D each stand for a different Single Digit. Use the clues below to find the digit. Use the clues to find the digits.

    Clues

    • C is greater than 1.
    • C is an odd number.
    • B and D are even Numbers.

    • CA + CB=DC

    What number does D Stand for?

    D stands for do your own fúcking homework.


  • Registered Users, Registered Users 2 Posts: 241 ✭✭Paddycrumlinman


    strobe wrote: »
    D = 2

    But it might not be the only answer.

    Explanation if possible Sir?


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  • Closed Accounts Posts: 7,872 ✭✭✭strobe


    Explanation if possible Sir?

    Blast my slow deletion skills. I was wrong.


  • Registered Users, Registered Users 2 Posts: 3,878 ✭✭✭irelandrover


    A=2, B=4, C=3, D=6


  • Closed Accounts Posts: 6,706 ✭✭✭Voodu Child


    Eleventy seven


  • Registered Users, Registered Users 2 Posts: 2,326 ✭✭✭Scuid Mhór


    A=2, B=4, C=3, D=6

    i FOR ONE welcome our new after hours crew homie.


  • Registered Users, Registered Users 2 Posts: 1,112 ✭✭✭flyton5


    there is no fun in that, flyton5. to make the after hours crew, you gotta be able to conquer every challenge presented to you. i advise you start trying to solve it instead of sitting on your moral pedestal.


    I prefer to stand on my moral pedestal. I left a high horse around here somewhere too...


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  • Registered Users, Registered Users 2 Posts: 3,205 ✭✭✭cruizer101


    C is greater than 1 and C is odd so that limits its to 3,5,7,9
    Considering the answer is a two digit number C has to be 3.

    Thirty something plus thirty something is sixty something so D is 6.

    A + B has to be less than 10 so is 2 & 4.


  • Closed Accounts Posts: 2,975 ✭✭✭W.Shakes-Beer


    A=2, B=4, C=3, D=6

    fine im gonna be immature and just laugh at that.





    C=3


  • Registered Users, Registered Users 2 Posts: 23,688 ✭✭✭✭mickdw



    • C is greater than 1.
    • C is an odd number.
    • B and D are even Numbers.

    • CA + CB=DC

    What number does D Stand for?

    D=6


  • Registered Users, Registered Users 2 Posts: 5,166 ✭✭✭enda1


    A=2, B=4, C=3, D=6
    cruizer101 wrote: »
    C is greater than 1 and C is odd so that limits its to 3,5,7,9
    Considering the answer is a two digit number C has to be 3.

    Thirty something plus thirty something is sixty something so D is 6.

    A + B has to be less than 10 so is 2 & 4.
    Brains of AH.... assistance is required.

    Brucy bonus point to the person who can explain the answer in simple terms.

    I had great success in the last one I posted.

    Thanks in Advance

    The letters A,B,C and D each stand for a different Single Digit. Use the clues below to find the digit. Use the clues to find the digits.

    Clues

    • C is greater than 1.
    • C is an odd number.
    • B and D are even Numbers.

    • CA + CB=DC

    What number does D Stand for?

    Guys above are right. D=6, but A=1, B=2, C=3


  • Registered Users, Registered Users 2 Posts: 434 ✭✭c-note


    CA+CB=DC:

    a = 1 b= 2 c=3 d=6

    OPTIONS
    a = 1,2,3,4,5,6,7,8,9
    b = 1,2,3,4,5,6,7,8,9
    c = 1,2,3,4,5,6,7,8,9
    d = 1,2,3,4,5,6,7,8,9

    TOLD C IS ODD > 1, B,D EVEN
    a = 1,2,3,4,5,6,7,8,9
    b = 2,4,6,8
    c = 3,5,7,9
    d = 2,4,6,8

    dc is an odd number (ends in odd number)
    cb is an even number (ends in even number)
    therfore ca must be odd-> a must be odd

    a = 1,3,5,7,9
    b = 2,4,6,8
    c = 3,5,7,9
    d = 2,4,6,8

    CA+CB=DC
    so D will be roughly twice C, only options are c=3 d=6

    a = 1,3,5,7,9
    b = 2,4,6,8
    c = 3
    d = 6

    now a+b = c (3)
    only options are 1,2

    a = 1
    b = 2
    c = 3
    d = 6


  • Registered Users, Registered Users 2 Posts: 241 ✭✭Paddycrumlinman


    c-note wrote: »
    CA+CB=DC:

    a = 1 b= 2 c=3 d=6

    OPTIONS
    a = 1,2,3,4,5,6,7,8,9
    b = 1,2,3,4,5,6,7,8,9
    c = 1,2,3,4,5,6,7,8,9
    d = 1,2,3,4,5,6,7,8,9

    TOLD C IS ODD > 1, B,D EVEN
    a = 1,2,3,4,5,6,7,8,9
    b = 2,4,6,8
    c = 3,5,7,9
    d = 2,4,6,8

    dc is an odd number (ends in odd number)
    cb is an even number (ends in even number)
    therfore ca must be odd-> a must be odd

    a = 1,3,5,7,9
    b = 2,4,6,8
    c = 3,5,7,9
    d = 2,4,6,8

    CA+CB=DC
    so D will be roughly twice C, only options are c=3 d=6

    a = 1,3,5,7,9
    b = 2,4,6,8
    c = 3
    d = 6

    now a+b = c (3)
    only options are 1,2

    a = 1
    b = 2
    c = 3
    d = 6


    Great explanation on this one. Thanks a million now I have to explain it to my 7 year old.... :eek:


  • Closed Accounts Posts: 4,204 ✭✭✭FoxT


    C >1
    C is odd
    C+C<10 since the answer is a 2-digit number.
    Therefore C=3



    D could be = C+C or C+C+1 if A+B >9

    BUT D is even, so it cannot be = C+C+1

    Therefore

    D=6



    A + B = C

    B is Even

    So A=1, B=2



    Verify:

    CA+CB=DC
    31+32=63

    Next!


    - FoxT


  • Registered Users, Registered Users 2 Posts: 1,184 ✭✭✭KINGVictor


    It is
    A-1
    b-2
    c-3
    d-6


  • Registered Users, Registered Users 2 Posts: 3,878 ✭✭✭irelandrover


    i see i got the right answer in the wrong way, i took the CA to mean C multiplied by A


  • Closed Accounts Posts: 20,739 ✭✭✭✭starbelgrade


    D = D


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  • Registered Users, Registered Users 2 Posts: 3,089 ✭✭✭ascanbe


    A to the B to the C to the D, Paddycrumlinman's heading for a Maths degree
    D to the C to the B to the A, the AH crew get solutions with a little delay


  • Closed Accounts Posts: 20,739 ✭✭✭✭starbelgrade


    ascanbe wrote: »
    A to the B to the C to the D, Paddycrumlinman's heading for a Maths degree
    D to the C to B to the A, the AH crew get solutions with a little delay

    Word.


  • Registered Users, Registered Users 2 Posts: 3,089 ✭✭✭ascanbe


    Word.

    True dat.


  • Closed Accounts Posts: 7,751 ✭✭✭Saila


    Great explanation on this one. Thanks a million now I have to explain it to my 7 year old.... :eek:

    now you can explain why your '7 year old' is up at 00:30, waiting for you to do his homework hmmm...


  • Closed Accounts Posts: 258 ✭✭Tiny Explosions


    Great explanation on this one. Thanks a million now I have to explain it to my 7 year old.... :eek:


    This seems like a fairly difficult math problem for a 7 year old!

    I'd hate to see his/her's maths homework questions when their 10 years old.:eek:


  • Closed Accounts Posts: 8,305 ✭✭✭DOC09UNAM


    Saila wrote: »
    now you can explain why your '7 year old' is up at 00:30, waiting for you to do his homework hmmm...

    The time is not the same for everyone.


  • Registered Users, Registered Users 2 Posts: 11,554 ✭✭✭✭alwaysadub


    OP-Does your son think you figure these out by yourself, or does he know you ask a load of Irish people on the internet for help? :D

    Thank fcuk i didn't go to school in America, cos they are hard questions for a 7year old!


  • Closed Accounts Posts: 22,559 ✭✭✭✭AnonoBoy


    "I beat the smart kids! I beat the smart kids!"


  • Registered Users, Registered Users 2 Posts: 3,089 ✭✭✭ascanbe


    alwaysadub wrote: »
    OP-Does your son think you figure these out by yourself, or does he know you ask a load of Irish people on the internet for help? :D

    Thank fcuk i didn't go to school in America, cos they are hard questions for a 7year old!

    If you'd asked me that when i was 7, i'd still be trying to figure it out now.


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  • Registered Users, Registered Users 2 Posts: 2,763 ✭✭✭Sheeps


    D = 7


  • Closed Accounts Posts: 804 ✭✭✭yerayeah


    CA+CB=CD

    CxD/B is odd by even so it's an even number.
    Therefore CA must be even as only two evens can give an even answer.
    Therefore A must be even as for CA to be even, A must be even as C is odd.

    C(A+B)=C(D)
    A+B=D

    Since they're all different numbers, only 2+4=6 fits the bill, so D=6 and you don't know what the rest are. My take on it anyway!


  • Registered Users, Registered Users 2 Posts: 168 ✭✭bowsie010


    Your child gets some faarce hard homework.


  • Registered Users, Registered Users 2 Posts: 1,922 ✭✭✭fergalr


    Sometimes searching problems like this are best solved on computer.
    Computers are good at trying a lot of combinations of something fast.

    • C is greater than 1.
    • C is an odd number.
    • B and D are even Numbers.

    • CA + CB=DC
    Here are some numbers that meet those criteria, assuming CA doesn't mean C*A, but instead A concatenated onto C:
    1,0,1,2
    1,0,21,4
    1,2,3,6
    1,2,63,12
    1,4,5,10
    1,6,7,14
    1,8,9,18
    1,10,1,12
    1,12,3,34
    1,14,5,56
    1,16,7,78
    1,20,31,34
    1,22,53,58
    1,24,75,82
    1,30,1,14
    .
    .
    .
    3,0,3,6
    Single Digit:

    1,0,1,2
    1,2,3,6
    3,0,3,6
    different Single Digit

    1,2,3,6


    Numbers in the range -9 <-> 0 don't satisfy it either.
    Have to say, its actually quite robustly specified for a problem like this!


  • Closed Accounts Posts: 7,134 ✭✭✭x in the city


    fergalr wrote: »
    Sometimes searching problems like this are best solved on computer.
    Computers are good at trying a lot of combinations of something fast.



    Here are some numbers that meet those criteria, assuming CA doesn't mean C*A, but instead A concatenated onto C:
    1,0,1,2
    1,0,21,4
    1,2,3,6
    1,2,63,12
    1,4,5,10
    1,6,7,14
    1,8,9,18
    1,10,1,12
    1,12,3,34
    1,14,5,56
    1,16,7,78
    1,20,31,34
    1,22,53,58
    1,24,75,82
    1,30,1,14
    .
    .
    .
    3,0,3,6



    1,0,1,2
    1,2,3,6
    3,0,3,6



    1,2,3,6


    Numbers in the range -9 <-> 0 don't satisfy it either.
    Have to say, its actually quite robustly specified for a problem like this!

    surprised of the intelligence of (some) of the ah motley crew tbh...:P


  • Registered Users, Registered Users 2 Posts: 2,670 ✭✭✭Doc


    I was always told that if you have two numbers represented by letters such as A and B and you show them in a problem like this:

    AB + B = C

    The AB means that you multiply A by B.

    So that if A=4 and B=2 the above problem would be…

    (4x2) + 2 = C => C = 10

    The way you have solved OP's question this AB would be 42.

    So...

    42 + 2 = C => C = 44

    Which I believe is incorrect.

    Am I wrong???


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  • Registered Users, Registered Users 2 Posts: 4,378 ✭✭✭mojesius


    Thank jeebaz I don't have to do maths anymore.


  • Registered Users, Registered Users 2 Posts: 2,945 ✭✭✭D-Generate


    Wow some people went to such lengths to find out!

    C > 1 and C is odd leaving 3, 5 ,7, 9. Since we end up with a 2 digit number at the end after adding CA + CB then it can't be greater than 3.

    3A + 3B = D3

    Now to get 3 we have to add 1,2 or else we have a carry or we are using a 3 again in the case of 3,0.

    So A = 1, B = 2, C = 3 and D = 6.

    However this is supplementary to the answer as the question only asks for D so answer is D is 6.

    I am gutted that i figured it out in no time at all and was excited to be first to have the answer but alas was stripped of this accolade.


  • Registered Users, Registered Users 2 Posts: 2,945 ✭✭✭D-Generate


    Doc wrote: »
    I was always told that if you have two numbers represented by letters such as A and B and you show them in a problem like this:

    AB + B = C

    The AB means that you multiply A by B.

    So that if A=4 and B=2 the above problem would be…

    (4x2) + 2 = C => C = 10

    The way you have solved OP's question this AB would be 42.

    So...

    42 + 2 = C => C = 44

    Which I believe is incorrect.

    Am I wrong???

    Well if you did it that way then wouldn't it be
    C(A + B) = C(D)
    A + B = D

    4, 2, 6
    6, 2, 8
    2, 4, 6
    2, 6, 8

    So those are the valid solutions in that instance that satisfy criteria.


  • Registered Users, Registered Users 2 Posts: 2,670 ✭✭✭Doc


    D-Generate wrote: »
    Well if you did it that way then wouldn't it be
    C(A + B) = C(D)
    A + B = D

    4, 2, 6
    6, 2, 8
    2, 4, 6
    2, 6, 8

    So those are the valid solutions in that instance that satisfy criteria.

    That’s my point you took CA + CB=DC to mean (C is the first part of the number with A as the second) plus (C as the first part of the number with B as the second) is equal to (D as the first part of the letter with C as the second) then you can come up with a definitive answer for the value of D.

    yerayeah's way of answering is correct. You got the right answer but the wrong way


  • Registered Users, Registered Users 2 Posts: 2,997 ✭✭✭Adyx


    D-Generate wrote: »
    Wow some people went to such lengths to find out!

    C > 1 and C is odd leaving 3, 5 ,7, 9. Since we end up with a 2 digit number at the end after adding CA + CB then it can't be greater than 3.

    3A + 3B = D3

    Now to get 3 we have to add 1,2 or else we have a carry or we are using a 3 again in the case of 3,0.

    So A = 1, B = 2, C = 3 and D = 6.

    However this is supplementary to the answer as the question only asks for D so answer is D is 6.

    I am gutted that i figured it out in no time at all and was excited to be first to have the answer but alas was stripped of this accolade.

    If A = 1, B = 2, C = 3 and D = 6, that implies 3*1 + 3*2 = 3*6. Since 9 ≠ 18, the only solution which satisfies the equation and the clues is A=2, B=4, C=3, D=6 which was pointed out several times already. You can check it on WolframAlpha.


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  • Closed Accounts Posts: 8,305 ✭✭✭DOC09UNAM


    Adyx wrote: »
    If A = 1, B = 2, C = 3 and D = 6, that implies 3*1 + 3*2 = 3*6. Since 9 ≠ 18, the only solution which satisfies the equation and the clues is A=2, B=4, C=3, D=6 which was pointed out several times already. You can check it on WolframAlpha.

    Your not multiplying them at all. You are told the letters stand for digits, not numbers.


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