Confusing permutation? Or combination? Is this problem a permutation or combination problem? My idea is that this is permutation but Im not that sure... any idea to solve this problem? I tried putting the first $3$ company in $3^3$ possible ways that is $27$, but i got boggled on the remaining $2$ organizations because of the given condition... 
There are 5 student organizations. How many ways can 3 students join these organizations if no 2 students can join the same org? Thank you 

Since the students are distinguishable, it is a permutaiton problem. 
It is just $\frac{5!}{(5-3)!}$.
You can also think of it as first out of the $5$ companies, choose $3$ companies and then rearrange the students.
$$\binom{5}{3} \times 3!.$$
Remark: $3^3$ doesn't seem to avoid the constraint that no $2$ students can join the same org.
