00:01
So we're doing margin of error here.
00:02
I've gone ahead and written out the formula here.
00:05
The margin of error is equal to 2 times the square root of p, which is the percentage that we're going to be given, then times the quantity of 1 minus that same p, divided by n, which is our sample size.
00:20
In this problem's case, we don't even have to search for that information.
00:24
It's just straight up telling us what p and n are.
00:28
So that's very nice to them.
00:31
Do make sure you remember that whenever the problem tells you here that p is equal to 31%.
00:38
That is useful information, but that's not what we're actually going to plug into the formula.
00:43
We don't plug percentages straight into a formula ever in math.
00:47
We always need to change it back to decimal form, okay? meaning, remember that percent literally means divide by 100.
00:55
So if you ever want to change a percent to a decimal, divide that number by.
00:58
By 100.
00:59
31 divided by 100 is 0 .31...