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Topic: Finding A, B, and C
Replies: 4   Last Post: Jan 21, 2005 6:12 PM

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Posts: 1
Registered: 1/25/05
Re: Finding A, B, and C
Posted: Jan 21, 2005 3:10 PM
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On Sun, 02 Jan 2005 21:39:58 GMT, N. Silver wrote:
>Sylvain Croussette answered on alt.math.undergrad:
>> st9468s4 (EJC) wrote:
>> ABC I have to find the values of A, B and C where A>B>C
>>- CBA
>>= CAB

>Assuming A,B and C are single digits:
>Rewrite as:

>>From the 1st column: B+A=C, or B+A=C+10, if there is a carry.
> From the 2nd column also A+B=B; this is the same as the 1st column
>so it's impossible, unless there is a carry from the 1st; so it's
>1+A+B=B+10, because A+B produced a carry in the 1st column.
> From the third column 1+C+C=A.
>Rewrite these equations:
>1) A+B-C=10
>2) A+B-B=9
>3) A-2C=1
>Clearly from equation 2, A=9, so from equation 3, C=4 so B=5.

I was wondering where did 10 come from? Is it just some kind of random
number you pick because I have been working on a very similar equation


the answer is alike, A=4 B=5 C=9.
Could you also tell me what kind of method are you using, I've tried
with substitution, elimination, division, etc

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