So you have 7 seats, and 6 students. So you can try to assign seats to students. The first student will have 7 options, the second will have 6, and so on.
Does that help?
is it 7!?
the formula to find the answer?
So in a question like this, you multiply the first number of possibilities by the remaining number by the remaining, until you are out. In this case, you have 6 students, so 6 slots:
_ * _ * _ * _ * _ * _
The number of possibilities decreases by one each time, so fill in the blanks:
7 * 6 * _ * _ * _ * _