Question 164484

Let x=volume of the original solution
Now we know that the amount of pure acid in the original solution (0.20x) plus the amount of pure acid added (0) has to equal the amount of pure acid in the final solution (0.15(5+x)).  So our equation to solve is:

0.20x=0.15(5+x)  get rid of parens (distributive law)
0.20x=0.75+0.15x  subtract 0.15x from each side
0.20x-0.15x==0.75+0.15x-0.15x
0.05x=0.75  divide each side by 0.05
x=15 liters-----------------------------------volume of original solution
CK
0.20*15=0.15*20
3=3


Hope this helps---ptaylor