PUZZLEBOXX

If 3 reds = yellow then red can only be 1, 2 or 3, which means yellow would be 3, 6 or 9.

But the bottom sum tells us that yellow cannot be 6 or 9 (because 3 x 6 = 18 and 3 x 9 = 27).

Therefore yellow must be 3 and red must be 1.

The rest should be easy.

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