00:01
We are told that 44 % of people say they are in excellent health, which simply means p of, let's say, excellent health is 0 .44, which implies p of not excellent health is 1 minus that, so 0 .56.
00:30
So here then is a binomial type problem.
00:33
We have success and failure.
00:35
Success here is being healthy, failure being not healthy.
00:40
Now, i want to work out the chance of 14 adults, more than three, will say they are in excellent health.
00:50
Now, for this, we work backwards.
00:53
We do 1 minus p of what you don't want is 3 or less in excellent health.
01:03
So p of x bigger than 3, same thing as 1 minus p of x less than or equal to 3.
01:10
Why do that? because then you can use the calculator, ti84 plus, as 1 minus, and the function you need is called binom, c for cumulative, cdf.
01:24
And you'll find that function by pressing 2nd, followed by vars, v -a -r -s, on the right, just below the arrow keys.
01:34
That brings up the menu for distributions.
01:37
You can't see it yet.
01:38
Go down past number 9 at the bottom...