Question 296046
Your problems are a great example for the website rules 
one problem at a time. Your problems  belong in different categories.
One is a distance problem and one is  a mixture problem
This can be solved from the view of the insecticide or from the view of the water
First the insecticide.
11*.6=(11+w)*.02
w=319 quarts of water
Notice there is nothing added on the left. Why ? because water has 0% insecticide and 0*w=0
so from the view of the water.
60% insecticide has 40 percent non insecticide.
.4*11+w=(11+w)*.98
319 quarts of water
Using both methods is a good check on your percentages.
Let's say you put .2 instead of .02 the results would not match.
That is quite a reduction from 60% to 2 percent. Are you sure that is right? not 20 percent?