Combinatorics
Arrangements
Easy
Non-Adjacent Books
Five distinct books are placed on a shelf. Two particular books must not be adjacent. How many valid arrangements are there?
Quant interview-style problem · QS-C004
Question 7 of 60
Five distinct books are placed on a shelf. Two particular books must not be adjacent. How many valid arrangements are there?
Think first. Use hints deliberately. Study the reasoning only when you need it.