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We looked at the number on each domino first and knew the that number needed to be reasonably big. We placed the dominoes down and started to add each side up. When we first started, one side was much bigger than the other. We then realised that we needed to spread the 6's around to balance each side. In our final solution, we have a 6 on three of the four sides.

We kept swapping around the tiles until we were incredibly close. At first we thought the total was 11, however it didn't balance. So we swapped around the tiles some more and rotated them.

Our final answer is 12 on each side!