Question 966356
From 2 large vessels of hydrochloric acid, labeled 15% acid and 20% acid, Kim Ekol must create 20 liters of 18% acid solution. How many liters of the 15% acid solution should she use? 
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let x=amt of 15% solution Kim should use
20-x=amt of 20% solution Kim should use
15%x+20%(20-x)=18%*20
.15x+4-.20x=3.6
.05x=0.4
x=8
How many liters of the 15% acid solution should she use? 8