0:00
Okay.
00:02
This question has us using four letter call stations and determining how many possibilities we have in different scenarios.
00:10
So the first part says that the first letter has to be either a k or a w with no repeat letters.
00:21
So we have four different spots here.
00:25
And in our first spot, we either have a k or a w.
00:29
So it means we only have two options.
00:30
But then for our next spot, we can pick everything except that previous letter because it says no repeats.
00:42
So we have 25 spots here.
00:44
And then similarly, we have 24 spots in the second spot and 23 in the final last spot.
00:53
So multiplying all these together, we get 2760 for the total number of combinations of letter stations.
01:11
Then, for the next part, it says repeats are allowed, but the first letter is k or w.
01:23
So this is very similar to the last one, except now that we have repeats...