00:01
Hello, so here we're looking at the word optical.
00:03
So o -p -t -i -c -a -l.
00:06
Wanna know how many ways the letters can be arranged such that the vowels are going to be together.
00:11
Well, the vowels here are gonna be o -i -n -a.
00:13
We can go ahead and treat those as like a single letter.
00:16
And then we have five letters here.
00:19
So the number of ways to arrange five letters is, well, five times four times three times two times one ways, or five factorial.
00:28
So there's five factorial ways here, which is going to be, well, five times four times three times two times one, is going to be equal to 120...