Respuesta :
220, because each student, can write
12 and choose 3 possible combination of reports which is n!(n−k)!k!=220.
Answer with explanation:
Number of students in freshman class = 160
Total number of novels = 12
As, each freshman must write 3 reports , means selecting 3 novels out of 12 novels.
As,selection means order of choosing novels is not important.
So, we will apply rule of combinatorics here.
Selecting 3 novels out of 12 novels , is different combinations of novels that a freshman student can choose to write reports on is given by
[tex]_{3}^{12}\textrm{C}\\\\=\frac{12!}{(12-3)!3!}\\\\=\frac{12!}{9!\times3!}\\\\=\frac{12*11*10*9!}{9!*3*2*1}\\\\=11*10*2=220[/tex]
Option B:220
