Question

The number of different words that can be formed using all the letters of the letters of the word $COCACOLA$ with start and ends with $O$ is

• A. $840$
• B. $420$
• C. $120$
• D. $60$

Answer 1

The correct option is C $120$

As word starts and ends with O, 6 letters remain to arranged with C repeated thrice.

Therefore total no. of possible arrangements

$=\frac{6!}{3!}=\frac{6\times 5\times 4\times 3!}{3!}=6\times 20=120$