OEYou can solve this problem by using the Anagram method. Five people (call them A through E) will be assigned to seats (designated as 7, 2, and 3), with 2 people left without a seat (designated as N)
Attachment:
screenshot.1180.jpg [ 13 KiB | Viewed 959 times ]
The total number of possibilities is the number of arrangements of the “word” \(123 N N\), which yields the same formula as above: 5 items, so 5!, divided by a factorial for all “repeats.” The N is listed twice, so the correct expression is 5!/2!