Step 1 :The given expression is a permutation, which is a way of arranging items where the order is important. In this case, we are asked to find the number of ways to arrange 8 items out of 18.
Step 2 :The formula for permutation is: \(P(n, r) = \frac{n!}{(n-r)!}\) where n is the total number of items, r is the number of items to choose, and '!' denotes factorial, which is the product of all positive integers up to that number.
Step 3 :So, we need to calculate the factorial of 18, the factorial of (18-8), and then divide the first by the second.
Step 4 :Let's calculate: n = 18, r = 8, factorial_n = 6402373705728000, factorial_n_r = 3628800
Step 5 :Then, calculate the permutation: permutation = 1764322560.0
Step 6 :Final Answer: The permutation of 18 items taken 8 at a time is \(\boxed{1764322560}\).