If this sum is correct, what digits do A and M represent? MA + A = AM

(In reply to re(2): Solution by e.g.)

I agree e.g., I was confused about why A+A=10+M as well.

I solved it your first way (10M + A + A = 10A + M), but I just had to say something for completeness...

I need to say the REASON why the only possible answer is M=8 and A=9 (without going through trial and error).  Rearranging 9M=8A as M=A*8/9, we see that in order for M to be an integer, A must be a multiple of 9.  The only single digit multiple of 9 is 9.  So A=9, making M=8.

(I could have done the same thing with A=M*9/8, and then M must be a single digit multiple of 8, which is 8.  Same thing)

Sorry for being anal, but I just couldn't let it get glossed over =)

Posted by nikki on 2004-12-29 16:03:31