00:01
To begin this problem, we are told that you have 0 .4 milligrams of nicotine absorbed into the blood.
00:07
Now, every hour, 35 % of it is going to be washed out of the blood.
00:11
So the first thing we want to do is create an equation.
00:14
So the equation we're going to be doing since we're given a rate is going to be that the amount is equal to the original amount.
00:20
So we'll say a sub zero.
00:22
And then it'll be one minus r since it's leaving.
00:25
And then since it's every hour, it's just going to be exponent of t.
00:28
So what we have here is the original amount is going to be 0 .4, and then we're going to do 1 minus the 0 .35 for the 35 % to the t power.
00:39
Now it's always proper form for us to go ahead and simplify what's going on on the inside here.
00:44
So our final equation, let me double check there.
00:47
We're going to do is n it looks like.
00:48
So instead of a, let's go ahead and change this to say n.
00:53
So it'll be n equals instead.
00:55
Will be n is equal to 0 .4, and then when you subtract here, you get 0 .65 and then to the t...