One hundred liters of a 57.84% acid solution is obtained by mixing a 75% solution with a 42% solution. How many liters of each must be used to obtain the desired mixture?

A) 40 liters of 75% acid and 60 liters of 42% acid

B) 53 liters of 75% acid and 47 liters of 42% acid

C) 58 liters of 75% acid and 42 liters of 42% acid

D) 43 liters of 75% acid and 57 liters of 42% acid

E) 48 liters of 75% acid and 52 liters of 42% acid

1 answer

.75 x + .42 y = .5784 (100)
x+y = 100
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.75 x + .42 y = 57.84
.75 x + .75 y = 75
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-.33 y = - 17.16
y = 52
x = 48
E