There are 1560 ways
Explanation:
The toal number of restaurants are 8, out of which 3 serve seafood, and during the summer gateway, Jason decided to dine out at 4 multifarious restaurants.
Since, the order is significant, permutations is to be used.
Four restaurants can be chosen from the 8 restaurants in [tex]_{8} \mathrm{P}^{4}[/tex]. In this case, "at least one" is complement of "fewer than one" (that is 0). Thus, four restaurants that are not serving seafood can be chosen from five restaurants in [tex]5 P^{4}[/tex].
Using complements principle to get the number of ways to get at least one of the restuarants serve seafood,
[tex]8 P^{4}-5 P^{4}[/tex] = 1680-120
[tex]8 P^{4}-5 P^{4}[/tex] = 1560
Therefore, there are 1560 ways