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

$63$

Explanation for the correct option:

Determine the number of ways, one or more books can be chosen.

The number of ways of choosing no book is given by:${}^6{C}_0$ which is $=1$

We have a total of $6$ books, which can be chosen in a total of $2^6$ ways.

Therefore, the number of ways one or more books can be chosen is given as follows:

(Total number of ways of selecting a book $-$ Number of ways of not selecting any book).

$$\begin{gathered} =2^6-1 \\ =64-1 \\ =63 \end{gathered}$$

Hence, The correct answer is option (B)