<PRE><B>Question 1160466</B>
&lt;br&gt;
A traditional algebraic solution would start something like this:&lt;br&gt;
x = ml of 2% alcohol
100-x = ml of 7% alcohol&lt;br&gt;
The amount of actual alcohol in the two ingredients is 2% of x ml, plus 7% of (100-x) ml; the amount in the mixture is 5% of 100ml:&lt;br&gt;
{{{.02(x)+.07(100-x) = .05(100)}}}&lt;br&gt;
That equation is easily solved using basic algebra.  I leave it to you to do that.&lt;br&gt;
Here is what is almost certainly the fastest and easiest way to solve a mixture problem like this.&lt;br&gt;
Consider the three percentages on a number line -- 2, 5, and 7.  Observe that 5 is 3/5 of the way from 2 to 7.&lt;br&gt;
That means 3/5 of the mixture is the 7% alcohol.&lt;br&gt;
3/5 of 100 ml is 60 ml.&lt;br&gt;
ANSWER: 60 ml of 7% alcohol, 40 ml of 2% alcohol.&lt;br&gt;
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