00:01
In this situation, they tell us that 70 % of people who went to the store make a purchase and three customers enter the store, and they want to know the probability that one of the three customers make a purchase.
00:14
So in this case, what we have is a binomial situation.
00:17
The customers either buy or don't buy, and there's a fixed probability that they will buy.
00:23
So in this case, what they want to know is the probability that x is equal to two, in a binomial situation with n equals to three and a probability of purchasing 0 .7.
00:36
So to do that, the best way to do it is with a calculator.
00:40
You go to a graphical calculator of any type.
00:44
In this case, we're going to use a ti84, which is a very popular high school calculator.
00:49
And here we're going to go to distributions.
00:51
So we're going to go second distributions.
00:54
And here we're going to look for the binomial.
00:56
So the binomial pdf.
00:59
Because that's the one that gives us the binomial for a specific value, which in this case is x equals to 2.
01:06
So we run that.
01:08
The number trials is 3...