Question

in how many ways can a man invite at most 8 of his 9 friends to a party?

Answer 1

Answer:

Step-by-step explanation:

2^9  - 2 =512 - 2 ways = 510 ways

Each  friend have  2 chances   to be invited or not

so  2^9 ways  = 512 ways   that included  all  9 are invited and none of them

                                               are invited

   so    512 - 2  

      = 510 ways