SOLUTION: How many gallons of a 80​% antifreeze solution must be mixed with 80 gallons of 20​% antifreeze to get a mixture that is 70​% ​antifreeze? Use the​ si

Algebra ->  Customizable Word Problem Solvers  -> Unit conversion -> SOLUTION: How many gallons of a 80​% antifreeze solution must be mixed with 80 gallons of 20​% antifreeze to get a mixture that is 70​% ​antifreeze? Use the​ si      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 1107798: How many gallons of a 80​% antifreeze solution must be mixed with 80 gallons of 20​% antifreeze to get a mixture that is 70​% ​antifreeze? Use the​ six-step method.
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
What six steps?

x, how many gallons of 80% antifreez
PRESENT: 80 gallons of 20% antifreeze
WANT: 70% antifreeze


%2820%2A80%2B80%2Ax%29%2F%2880%2Bx%29=70, Basic Equation

-
20%2A80%2B80x=70%2A%2880%2Bx%29
2%2A80%2B8x=7%2880%2Bx%29
2%2A80%2B8x=7%2A80%2B7x
x=5%2A80
highlight%28x=400%29
Four Hundred Gallons of 80% material be added.

CHECK?
%2820%2A80%2B80%2A400%29%2F480
%282%2A80%2B8%2A400%29%2F48
70
okay