Question 451389
3 gals. of 10% solution=3x.1 or .3 gals pure acid.
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x+y=3
.20x+.05y=.3
20x+5y=30
5x+5y=15
15x=15
x=1
y=2
You need 1 gal. of 20% solution, and 2 gals. of 5% solution for the mix..