00:01
We have our bleach solution here, which is just 2 % bleach, and we want to raise this to 5 % bleach by draining some of our solution out and replacing it with pure 100 % bleach.
00:13
So let's set this up.
00:14
This is very clearly a mixture problem.
00:16
So we're going to have percentage times amount plus percentage times amount equals percentage times amount.
00:22
That's pretty vague.
00:23
Let me put this in more concrete terms.
00:25
So we have 2 % or 0 .02 times the amount that we start with, plus 100%, that is pure bleach, or 1 times the amount that we're going to add of pure bleach, should be equal to 5%, or 0 .05 times 100 gallons.
00:45
That is we want a full tank.
00:47
So what we need to find is these amounts here.
00:50
We need amounts that we can multiply or that can add together to equal 100, and also that we can multiply by these percentages to make everything add up correctly.
01:01
So let's say that we're going to add in x gallons of pure bleach...