Question 1102865
We want to know how many mL. at 30% to mix with 80%.
We need a total of 625 mL. at 60%

Using the method of alligation.
<pre>
80         30 30/50*625=375 mL of 80% solution
      60     375+250= 625 mL of 60% solution
30         20 20/50*625=250 mL of 30% solution
           50
</pre>