Lyssa got 75 x 20/100 = <<75*20/100=15>>15 mistakes.
Lyssa's score is 75 - 15 = <<75-15=60>>60.
The score of Precious is 75 - 12 = <<75-12=63>>63.
Thus, Lyssa got 63 - 60 = <<63-60=3>>3 more correct answers than Precious.
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