Question 321528
A mixture of 14% disinfectant solution is to be made from 10% and 20% disinfected solutions. How much of each solution should be used if 20 gallons of 14% solutions are needed?

10% solution be x gallons
20% solution will be 20-x gallons
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Total 14% solution 20 gallons
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Concentration eauation 
0.1x+0.2(20-x)=20*0.14
0.1x+4-0.2x=2.8
-0.1x= -1.2
x= -1.2/ -0.1
x= 12 gallons of 10% solution
Balance 8 gallons will be 20% solution