Question

12 elevi si 3 profesori in cate moduri se va forma o echipa din 10 elevi si un profesor care va fi formula cu combinari?

Answer 1

   
[tex]\displaystyle \\ n = C_{12}^{10} \times C_{3}^{1} = C_{12}^{(12-10)} \times C_{3}^{1} = \\ \\ =C_{12}^{2} \times C_{3}^{1} = \frac{12 \times 11}{1\times 2} \times \frac{3}{1} =66 \times 3 = \boxed{198~moduri}[/tex]