SOLUTION: Mary is expirimenting with chemical in the laboratory. She mixes a solution that is 10% acid with a solution that is 25% acid. How much of the 10% acid solution will be needed to m

Algebra ->  Customizable Word Problem Solvers  -> Mixtures -> SOLUTION: Mary is expirimenting with chemical in the laboratory. She mixes a solution that is 10% acid with a solution that is 25% acid. How much of the 10% acid solution will be needed to m      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


   



Question 265583: Mary is expirimenting with chemical in the laboratory. She mixes a solution that is 10% acid with a solution that is 25% acid. How much of the 10% acid solution will be needed to make 50 liters of aolution that is 20% acis?
Answer by palanisamy(496) About Me  (Show Source):
You can put this solution on YOUR website!
Let x litres of 10% acid solution be mixed with y litres of 25% acid solution.
The resulting solution is of 50 liters of 20% acid solution.
So we have, x+y = 50 ...(1)
And, x*(10/100)+y*(25/100) = 50*(20/100)
10x+25y = 1000 ...(2)
(1)*10=> 10x+10y = 500 ...(3)
(2)-(3)=> 15y = 500
y = 500/15
y = 33 1/3 liters
(1)=> x+33 1/3 = 50
x = 50-33 1/3
x = 16 2/3 litres