Similar to this question: Probability Question - An elevator & 5 Passengers
Five people enter an elevator in the basement of a seven story building (ie. the building has a basement, plus floors 1-7). Each person independently selects one of the seven floors at random. No new people get on the elevator.
How likely it is that 3 passengers get off on one floor, and the remaining 2 get off on a different floor but also together?
I thought I could do:
(C(5,3) * 7 * C(2,2) * 6)/7^5
= 0.025 or %2.5
Is this correct?