00:01
In this question, we're given a large store.
00:03
1 quarter of all customers who go to the service department ask for help finding an item.
00:09
The next four customers are considered.
00:12
Then let x be the number of customers out of this sample of four who go to the service department will ask for help finding an item.
00:20
Now, n, the number of trials will be four.
00:23
In each trial, we take a look at a customer in this sample and see whether he or she will go and ask for help.
00:30
Now, these four trials are all identical.
00:37
They're all independent.
00:39
And in each trial, there's only one or two possible outcomes, success or failure.
00:45
Success would be a customer go to the service department will ask for help.
00:51
Failure would be he or she will not ask for help.
00:54
And p, probability of success in a single trial, that's probability a customer who go to the service department ask for help.
01:02
And that would be 1 quarter...