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Keep sending us YOUR OWN alphanumerics and we'll publish them in collections from time to time. The following two came from Jonathan Gill, St Peter's College, Adelaide, Australia.


There is a onetoone correspondence between digits and letters, each letter stands for a single digit and each digit is represented by a single letter. How many different solutions can you find?
Ling Xiang Ning(Allan) form Tao Nan School, Singapore, who solves many of are hardest problems, has sent 7 solutions to CARAVAN and 88 solutions to AUSTRALIAN. Is this all there are? Here is one solution to each.
76  968  
+86  +529  
    
162  1497 
Soh Yong Sheng, age 12, also from Tao Nan School, Singapore has sent this solution for.
NRICH  +  STARS  =  MATHS 
17230  +  48574  =  65804 
and there are al lot more.
We have the following solutions from Allan Ling (Tao Nan School, Singapore): For the equation
M  A  T  H  
+  E  M  A  T 


I  C  A  L 
T has to be 9 or 0, in order for it to satisfy T+A=A. However if T=0, it is impossible, as H+0 is not L. So T has to be 9.
The following are the possible sums (total 59):
4891  5791  4791  2591  3491  2491  2491 
+2489  +2579  +3479  +4259  +2349  +6249  +3249 
7380  8370  8270  6850  5840  8740  5740 
4391  2391  3291  3291  3692  4592  5092 
+2439  +5239  +5329  +4329  +4369  +3459  +3509 
6830  7630  8620  7620  8061  8051  8601 
4092  3092  5893  1893  2793  1893  2793 
+3409  +5309  +1589  +4189  +5279  +5189  +1279 
7501  8401  7482  6082  8072  7082  4072 
1693  4593  5493  2493  1493  6093  1894 
+4169  +1459  +1549  +6249  +7149  +2609  +5189 
5862  6052  7042  8742  8642  8702  7083 
3794  2794  6594  5294  1094  1094  1094 
+2379  +5279  +1659  +1529  +7109  +6109  +5109 
6173  8073  8253  6823  8203  7203  6203 
4795  4795  3795  2795  1695  1095  1095 
+3479  +1479  +2379  +3279  +2169  +7109  +6109 
8274  6274  6174  6074  3864  8204  7204 
1896  2496  1296  1096  1096  2197  1097 
+2189  +1249  +7129  +7109  +3109  +3219  +4109 
4085  3745  8425  8205  4205  5416  5206 
1097  1498  3298  1298  2198  4098  3098 
+3109  +2149  +1329  +5129  +3219  +2409  +2309 
4206  3647  4627  6427  5417  6507  5407 
2098  1098  1098  1098  
+4209  +5109  +4109  +3109  
6307  6207  5207  4207  
Jonathan also proved that the following alphanumeric does not work, that is it cannot have any solutions. Well done Jonathan.
N  R  I  C  H  
+  M  A  T  H  S 


S  T  A  R  S 
If it was an alphanumerics then H = 0 to satisfy 0 + S = S, but then H cannot be zero, otherwise C + 0 (H) = C and not R. We know that C and R cannot both represent the same number therefore
N  R  I  C  H  
+  M  A  T  H  S 


S  T  A  R  S 
cannot be made into an alphanumeric.