Several students are studying together for an exam. 60% of the students who studied less than 10 hours a week feel unprepared. 80% of students who studied 10 hours or more each week feel prepared. If 75% of the students studied less than 10 hours per week, what percent of the students feel prepared for the exam?

A. 20
B. 25
C. 30
D. 35
E. 50

Made the same calculation

The answer is missing from the options.

Let's say there are 100 students.

Students who studied <10 hrs = 75% = 75
So students who studied =>10hrs = 25

Given: 60% of the students who studied less than 10 hours a week feel unprepared.
So 40% of 75 (=30) feel prepared

Given: 80% of students who studied 10 hours or more each week feel prepared.
So 80% of 25 (= 20) feel prepared

Total (30 + 20) = 50 out of 100 feel prepared. 50% feel prepared
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