In her hamper, Brie has 12 x 75% = <<12*75*.01=9>>9 blouses.
In her hamper, she has 6 x 50% = <<6*50*.01=3>>3 skirts.
In the hamper, she has 8 x 25% = <<8*25*.01=2>>2 slacks.
She will need to wash 9 + 3 + 2 = <<9+3+2=14>>14 pieces of clothes.
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