Combining Monday and Tuesday, they raked 5 + 3 = <<5+3=8>>8 bags of leaves.
They earned 8 * $4 = $<<8*4=32>>32 for the first two days.
O for Wednesday's work they earned $68 - $32 = $<<68-32=36>>36.
Thus, they raked $36 / $4 = <<36/4=9>>9 bags of leaves on Wednesday.
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