Solution
Step-by-step explanation:
If order is important, permutations can be used to find the number of ways the event can take place
Number of ways to select any 5 out of 8 in a particular order = 8P5
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

Number of restaurants serving seafood = 2 , Number of restaurants not serving seafood = 3
Number of selections in which all restaurants do not serve seafood = 5P3 = 20
Number of ways such that at least one of the selected restaurants will serve seafood = Total number of selections - Number of selections in which all restaurants do not serve seafood
