Question

The number of ways in which 9 flowers, of which 5 are identical and white, and the other four are of different colours, can be set on garland so that no two of the coloured flowers are consecutive, is

• A. $60$
• B. $120$
• C. $180$
• D. none of these

Answer 1

The correct option is D none of these

It is a circular permutation,

So, (5 of them are identical)

$=\frac{8!}{2.5!}$

$=\frac{\mathrm{8.7.6}}{2}$

$=\mathrm{4.7.6}$

$=168$