Is the OA D?

Assuming the question is just to find out how many ways can atleast one person be called out of 8,

8C1 + 8C2 + 8C3 + 8C4 + 8C5 + 8C6 + 8C7 + 8C8

255?

ways to call atleast 1 = (2^n) - 1
in this case its 2^8 - 1 = 256-1 = 255
hence D

sanju09 wrote:Victor has 8 associates. In how many ways can he call one or more of them to banquet?
(A) 8
(B) 63
(C) 64
(D) 255
(E) 256



Made up

for every associate there are two options either he/she will be called or won't be called at banquet.
as there are 2 options for every associate therefore total no. of ways of inviting 8 associates will be 2^8. now here i have to subtract one case at which none of them will be called. so total no. of ways of inviting the 8 associates will be 2^8-1 that is 255.
hence [spoiler]D
[/spoiler]

yes should be 255

(2^n)-1 ( where n=8)