Trebling
3,6,9,12,15,18,21,24,27
First we knew that we only needed a 3x tables from 3-27, 30 and above would all be to much because you cannot have more 1 digit in the problem. So the first problem you have to solve is, Ex3 which needs to end in 1, so you look back to the 3x tables and the only possible answer is 21. So you carry on the 2 to the next letter which is Dx3 which e=7 so Dx3 must be 5 and add the 2 from the last problem, so D=5. So you carry the one to the Cx3. We then worked out that C=8, B=2, A=4.
1 a b c d e
x 3
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4 2 8 5 7 1