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The professors of a certain "Terror Subject” declared that if 70% is the passing raw score for their subject, only 40% of the students taking said subject would pass. They also added that the current 50% passing raw score resulted in 30% of the students to fail, which was acceptable to the university standards. What is the mean raw score (to two decimal place) of the 63.4851 students taking the subject? What is the standard deviation (to two decimal place) of 25.7153 the students taking the subject? Two equations two unknowns for Z=(X-u)/o