SOLUTION: Write a system of two equations using x and y to represent the following problem. A chemist is mixing two solutions together. The chemist wants 100 gallons when complete. He is m

Algebra ->  Systems-of-equations -> SOLUTION: Write a system of two equations using x and y to represent the following problem. A chemist is mixing two solutions together. The chemist wants 100 gallons when complete. He is m      Log On


   



Question 346645: Write a system of two equations using x and y to represent the following problem. A chemist is mixing two solutions together.
The chemist wants 100 gallons when complete. He is mixing a 24% solution with a 50% solution to get a 36% solution. How many gallons of each will he use?

Found 2 solutions by nerdybill, Fombitz:
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
Write a system of two equations using x and y to represent the following problem. A chemist is mixing two solutions together.
The chemist wants 100 gallons when complete. He is mixing a 24% solution with a 50% solution to get a 36% solution. How many gallons of each will he use?
.
Let x = amount of 24% solution
and y = amount of 50% solution
.
From: "The chemist wants 100 gallons when complete." we get equation 1:
x+y = 100
From: "He is mixing a 24% solution with a 50% solution to get a 36% solution." we get equation 2:
.24x + .50y = .36(100)
.
Solve equation 1 for y:
x+y = 100
y = 100-x
.
Substitute the above into equation 2:
.24x + .50y = .36(100)
.24x + .50(100-x) = .36(100)
.24x + 50-.50x = 36
50-.26x = 36
-.26x = -14
x = 53.85 gallons (of 24% solution)
.
to find 50% solution substitute above into equation 1:
x+y = 100
53.85+y = 100
y = 46.15 gallons


Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!

Let x be the amount of 24% solution.
Let y be the amount of 50% solution.
Volume equation:
1.x%2By=100
Concentration equation:
24x%2B50y=36%28x%2By%29=36%28100%29=3600
2.12x%2B25y=1800
From eq. 1,
x=100-y
Substitute into eq. 2,
12%28100-y%29%2B25y=1800
1200-12y%2B25y=1800
13y=600
highlight%28y=600%2F13%29gallons
Then from eq. 1,
x%2B600%2F13=100
x=1300%2F13-600%2F13
highlight%28x=700%2F13%29gallons