Question 633555
Mixture
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Amount=200L 
Concentration=62%=0.62


Solution A
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Amount = x 
Concentration =80% =0.8


Solution B
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Amount = 200-x 
Concentration =30% = 0.3



[Amount Solution A * Concentration A] + [Amount Solution B * Concentration of B] = [Amount of Mixture *Concentration of Mixture]
(x)(0.8)+(200-x)(0.3)=(200)(0.62)
0.8x+60-0.3x=124
0.5x=124-60
0.5x=64
0.5x/0.5=64/0.5
x=128



Chemist has to mix 128L of the 80% solution with 72L of 30% solution to get a 200L mixture of 62% acid solution..