In a friendship gang Andrew has 8 gang, in how many ways can he invite one or more of the gang to his house?
Pick one:  A) 200  B) 255  C) 260  D) 265  E) 290
Andrew can select one or more than one of his 8 gang.   =&gt; Required number of ways = 28 – 1= 255.   255
<result>B</result>
In a friendship gang Andrew has 8 gang, in how many ways can he invite one or more of the gang to his house?