How many ways can 6 people be seated in a row, if Ruth must be seated in the first chair?

Question

How many ways can 6 people be seated in a row, if Ruth must be seated in the first chair?

Answer 1

If Ruth must be seated in the 1st chair, then we essentially need to find how many ways that 5 people can be seated in the 5 remaining chairs.

This is:

(5)(4)(3)(2)(1) = 120 different ways