Dr. Graham currently has two acid solutions. She only has a 60% acid solution and a 20% acid solution in her lab. Dr. Graham needs 30 L of a 50% acid solution to conduct an experiment. How many liters of each solution should she mix together
+128406
Let x be the amount of the 60% solution in L
Let 30 - x be the amount of the 20% solution in L
So
.60x + .20(30 - x) = .50(30) simplify
.60x + 6 - .20x = 15
.40x + 6 = 15 subtract 6 from both sides
.40x = 9 divide both sides by .40
x = 22.5 = amount of 60% solution (in L)
30 - x = 7.5 = amount of 20% solution ( in L )
0.6x*0.2(1-x)=0.5
Factor out
0.6x*0.2-0.2x=0.5
Move x to one side
0.6x-0.2x=0.5-0.2
0.4x=0.3
x=0.3/0.4
x=0.75
So we need 0.75 of 60% solution and 0.25 (i.e 1-0.75) of 20% solution
+128406
Let x be the amount of the 60% solution in L
Let 30 - x be the amount of the 20% solution in L
So
.60x + .20(30 - x) = .50(30) simplify
.60x + 6 - .20x = 15
.40x + 6 = 15 subtract 6 from both sides
.40x = 9 divide both sides by .40
x = 22.5 = amount of 60% solution (in L)
30 - x = 7.5 = amount of 20% solution ( in L )
