Question

In how many ways can $20$ different colored beads can be strung on a necklace?

• A. $\frac{19!}{2}$
• B. $20!$
• C. $19!$
• D. $18!$

Answer 1

Answer: (A)

$\frac{19!}{2}$

With the given $20$ different colored beads ,according to circular permutation

Number of ways $=\frac{(20-1)!}{2}=\frac{19!}{2}$