Question 213292: How many gallons of a 4% acid solution should be mixed with 30 gallons of a 13% acid solution to obtain a mixture that is 7% acid? Found 3 solutions by checkley77, josmiceli, stanbon:Answer by checkley77(12844) (Show Source):
You can put this solution on YOUR website! .13x+.04*30=.07(30+x)
.13x+1.2=2.1+.07x
.13x-.07x=2.1-1.2
.06x=.9
x=.9/.06
x=15 gallons of 13% acid is used.
Proof:
.13*15+.04*30=.07(30+15)
1.95+1.2=.07*45
3.15=3.15
You can put this solution on YOUR website! Let = gallons of 4% acid solution to be added
In words:
(gallons of acid) / (gallons of solution) = 7%
given: = gallons of acid in 4% solution = gallons of acid in 13% solution = gallons of 7% solution
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60 gallons of 4% acid solution need to be added
check answer:
OK
You can put this solution on YOUR website! How many gallons of a 4% acid solution should be mixed with 30 gallons of a 13% acid solution to obtain a mixture that is 7% acid?
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Equation:
acid + acid = acid
0.04x + 0.13*30 = 0.07(x+30)
Multiply thru by 100 to get:
4x + 13*30 = 7x + 7*30
3x = 6*30
x = 2*30 = 60 (amt. of 4% solution needed for the mixture)
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Cheers,
Stan H.
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