
Steve S. answered 01/28/14
Tutor
5
(3)
Tutoring in Precalculus, Trig, and Differential Calculus
x = liters of original 10% citric acid.
3(20%) + x(10%) = liters citric acid
3 + x = total liters
(3(20%) + x(10%)) / (3 + x) = 13 / (102 + 13)
13(3 + x) = 115(3(20%) + x(10%))
39 + 13x = 115(3/5 + x/10)
39 + 13x = 23(3) + 11.5x
1.5x = 30
x = 300/15
x = 20 liters