Answer:
3 gallons
Step-by-step explanation:
Let
x ----> the amount of pure acid (100% solution) in gallons
Remember that



we know that

solve for x


therefore
3 gallons of pure acid should be mixed with 3 gallons of a 20% acid solution in order to get a 60% acid solution
Answer:
8, 6.
x=8 y=6
Step-by-step explanation:
-3 + 11 = +8
-5 + 11 = +6