The "remove 1" trick is sort of how I learned it, except instead of memorizing "2 goes with 7" I learned that the 2 digits should add back up to 9: 9*3 = 27

The "remove 1" trick is sort of how I learned it, except instead of memorizing "2 goes with 7" I learned that the 2 digits should add back up to 9: 9*3 = 27 (3-1 = 2,7 = 9-2) 9*4 = 36 (4-1 = 3,6 = 9-3) ... 9*9 = 81 (9-1 = 8,1 = 9-8) Fun stuff :)