A group of students is taking a CPR course. The total cost for the course is $275. The room in which the course will be held can
hold a maximum of 25 people, including the instructor. What is the minimum number of students needed to take the course so that the cost per student will be less than $15? A. 11 B. 17 C. 18 D. 19
lets say you want to sit x people around a table you would do x!. but since it doesn't count if you rotate the table you have to divide it by x, so the answer is x!/x = (x-1)!