Ten students are asked to visit a college admissions counselor. The counselor can meet with one student at a time. In how many ways can four time slots be assigned?
There are 10 choices for the student who will take the first time slot. After this, there are 9 choices for the student who will take the second time slot, 8 choices for the student who will take the third time slot, and 7 choices for the student who will take the fourth time slot. This gives us a total of $10\cdot 9 \cdot 8\cdot 7 = \boxed{5040}$ ways in which the time slots can be assigned.
