Question

You are rearranging your bookshelf to make it more interesting and harder to find anything on it. On one of the shelves you plan to put 13 biographies and 6 mysteries. How many ways can you arrange them on the shelf if you don't want any two mystery books next to each other (i.e. they need to be separated by at least one biography, maybe more...).

Answer 1

Answer:

for every 2 biographies you put 1 mystery book until you get to the middle then there will be 3

Step-by-step explanation: