Michelle used 3 * 8 = <<3*8=24>>24 cups of flour in the pasta dough.
She made 24 / 2 = <<24/2=12>>12 pounds of pasta dough.
She needs 12 / 3 = <<12/3=4>>4 drying racks for the pasta.
Thus, Michelle needs 4 - 3 = <<4-3=1>>1 more drying rack.
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