A laboratory technician needs to make a 39-liter batch of a 40% acid solution. How can the laboratory technician combine a batch of an acid solution that is pure acidwith another that is 10% to get the desired concentration?
+600 Let there be a liters of full acid, b liters of 10% acid. We have \(a+b=39, \frac{a+0.1b}{a+b}=0.4\rightarrow a+0.1b=15.6\rightarrow \boxed{a=13, b=26}\)
+36915 .10 (x) + 1.00 (39-x) = .40 (39)
-.9x = -23.4
x = 26 liters of 10% 13 liters of pure
