Milly and Floretta have a total of 3 packs of their own water balloons + 2 packs of the neighbor’s water balloons = <<3+2=5>>5 packs of water balloons.
So there is a total of 5 packs of water balloons * 6 balloons per pack of water balloons = <<5*6=30>>30 water balloons available.
As they split them evenly, they each have 30 water balloons / 2 = <<30/2=15>>15 water balloons.
After Milly steals some balloons, Floretta is left with 15 – 7 = <<15-7=8>>8 water balloons.
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