Sylvia got 50/5 = <<50/5=10>>10 incorrect answers.
This means she got 50 - 10 = <<50-10=40>>40 correct answers.
Sergio got 50 - 4 = <<50-4=46>>46 correct answers.
So, Sergio got 46 - 40 = <<46-40=6>>6 more correct answers than Sylvia.
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