Given:
The number of students in the class is n = 12.
The number of groups formed is k = 4
The number of students in each group is h = 3.
Explanation:
The formula for the number of ways to divide n students in k groups with each group has h students is,
[tex]\frac{n!}{(h!)^kk!}[/tex]
Substitute the values in the formula to determine the number of ways.
[tex]\begin{gathered} \frac{12!}{(3!)^4(4!)}=\frac{12!}{(3!)(3!)(3!)(3!)(4!)} \\ =15400 \end{gathered}[/tex]
So teacher can divide 12 students in 4 different groups such that each group has 3 students is 15400 ways.