Megan has 12 + 12 = <<12+12=24>>24 eggs
After making her omelet and cake, she was left with 24 - 2 - 4 = <<24-2-4=18>>18 eggs
After giving half to her aunt, she was left with 18/2 = <<18/2=9>>9
Megan would have 9/3 = <<9/3=3>>3 eggs per meal for the next three meals.
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