# Mai and books, again

**Discrete Mathematics**Level 3

After couple of days' break, Mai decided to continue with organising her home library. That means she will be doing the second bookshelf today (first one was done in the previous problem). Now, she has \( 9 \) books. Genres are **mystery**, **thriller** and **romance**, and from each genre, there are \( 3 \) books, one **red**, one **blue** and one **green** (for each genre). For today's arrangement, Mai wants to keep **every genre together** (she doesn't want to separate books with same genre) and also she doesn't want **same-coloured** books to be **neighbouring**. On how many ways can Mai organise the second shelf? Now, Mai knows the answer and she decided to help you (to some extent), so she offered a few answers. Only one is right.

**Important:** Like in the previous problem, two symmetrical arrangements are considered as \( 1 \) (123456789 is as same as 987654321).

To sum up:

**Your answer seems reasonable.**Find out if you're right!

**That seems reasonable.**Find out if you're right!

Already have an account? Log in here.