00:01
So in this problem, we have 4 liters of a 5 % bainberry solution.
00:15
And we want to add x liters of water to get a 3 % solution.
00:36
So let's take these percent solutions and turn them into percent water here.
00:46
So if it's 5 % bainberry, then it's 95 % water, which is written as 0 .95, right? if it's all water, then that's 100 % water, which is 1 .0.
01:09
And if it's 3 % solution, that's 97 % water, which is 0 .97.
01:17
So that now means that i could write this as a formula, right? i could take, if i just focus on the water here for a minute, 4 liters times 0 .95 plus x liters of water times 1 .0.
01:38
It's going to be equal to a 4 plus x, right? the total i have here will be 4 plus x times 0 .97 now, right? okay.
01:55
So let's multiply all this out.
01:58
And get all the x's on one side and the numbers on the other side...