00:01
So in this problem, we have a barrel over here, and it's got 20 gallons of water in it.
00:17
And we start pouring in a salt solution, and we're told that the amount of salt, q, at any point in time, is given by this equation, 6 times 1 minus e to negative 0 .06t.
00:40
Okay, and so we're asked after two minutes, so t is two minutes, what's q? what's the amount of salt in there? so q of 2.
01:01
All right, so this is 6 times 1 minus e, the negative 0 .06 times 2.
01:11
So that's 6 times 1 minus, so 0 .06 negative times 2 is negative 0 .12.
01:24
Take e to that power.
01:27
Let's attract that from 1.
01:31
Let's see, this is 0 .8111 .17...