Answer: 0.001389
Work Shown
1/720 = 0.001389 approximately
Step-by-step explanation
There's one correct alphabetical ordering of a collection of 6 books. That explains the 1 in the numerator.
The 720 in the denominator refers to the fact there are 6*5*4*3*2*1 = 720 different permutations of rearranging those 6 books. Another way to arrive at this value is to use the nPr formula with n = 6 and r = 6.