00:01
For this question, let's ask, so x is a binomial distribution with the total n and p.
00:08
So n here is equal to 20 and p is equal to the probability that an adult american operates the flusher of the toilets in public rooms with their foot.
00:20
So p here is 0 .64.
00:23
And the first question is about why this is binomial.
00:29
So the first thing is the 20 americans, they could be assumed or thought of as independent from each other.
00:44
And then for each american choosing, we have got two results.
00:56
The first one is yes, they use their foot to operate the flusher or no.
01:02
So we have got two possible outcomes.
01:07
And then three for each person, since they are randomly selected.
01:15
So the probability of yes, using foot to operate the flusher is equal to the national wide probability or the percentage, which is 0 .64.
01:30
So for each person, this p is equal to each other, which is equal to p...