SOLUTION: Is it possible to mix a 30% antifreeze solution with a 50% antifreeze solution and obtain a 70% antifreeze solution? Why or why not? I've tried making a table with the %s, bu

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Question 259795: Is it possible to mix a 30% antifreeze solution with a 50% antifreeze solution and obtain a 70% antifreeze solution? Why or why not?
I've tried making a table with the %s, but I can't understand it.
Found 2 solutions by richwmiller, Fombitz:
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
You can't make a solution that is more concentrated (stronger) than the strongest of the mixes. The strongest is 50% Nothing stronger than 50% without distillation.

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
No, the only mixtures you can obtain range from 30% to 50%.
30% means no 50% solution added to the mix.
50% means no 30% solution added to the mix.
Algebraically, let A be the # of gallons of 30% solution, B be the # of gallons of 50% solution.
Let's try to make 1 gallon of 70% solution.
A%2BB=1
30A%2B50B=70
From eq. 1,
A=1-B
30%281-B%29%2B50B=70
30-30B%2B50B=70
20B=40
B=2
Oops I need 2 gallons of B to make one gallon of 70% solution.
Now if you solve for A.
A=1-B=1-2=-1
Wow now I need -1 gallons, how do you do that?
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It's not possible, you need to increase the concentration of the solution to add least 70% or it won't work.