The ten $20 bills amount to $20 x 10 = $<<20*10=200>>200.
The eight $10 bills amount to $10 x 8 = $<<10*8=80>>80.
The four $5 bills amount to $5 x 4 = $<<5*4=20>>20.
So, Marly has a total of $200 + $80 + $20 = $<<200+80+20=300>>300.
Therefore, she will have $300/$100 = <<300/100=3>>3 pieces of $100 bills
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