CompTIA is a lot of MS in that they don’t disclose how they grade their exams (and they also include some questions that don’t count towards your score). For the Essentials, you need to get 700/900, and for 602/603/604 exams you need to score 725/900 (on a grading scale of 100-900).

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A+ IT Technician Certified – TechExams.net IT Certification Forums