Marge had 23 - 5 = <<23-5=18>>18 seeds grow into plants.
Rabbits ate 18 / 3 = <<18/3=6>>6 plants.
There were 18 - 6 = <<18-6=12>>12 plants left.
Weeds strangled 12 / 3 = <<12/3=4>>4 plants.
She had 12 - 4 = <<12-4=8>>8 plants left.
Marge kept 1 weed, so she ended up with 8 + 1 = <<8+1=9>>9 plants.
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