Question

Out of $6$ books, in how many ways can a set of one or more books be chosen

• A. $64$
• B. $63$
• C. $62$
• D. $65$

Answer 1

The correct option is B $63$

No. of ways of selecting no book $=6_{C_0}=1$

$\therefore$ No. of ways of selecting one or more book $=2^6-1=64-1=63$ [B]