SOLUTION: A chemical company makes two brands of antifreeze. The first brand is 55% pure antifreeze, and the second brand is 80% pure antifreeze. In order to obtain 170 gallons of a mixtur

Algebra ->  Customizable Word Problem Solvers  -> Mixtures -> SOLUTION: A chemical company makes two brands of antifreeze. The first brand is 55% pure antifreeze, and the second brand is 80% pure antifreeze. In order to obtain 170 gallons of a mixtur      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


   



Question 1138071: A chemical company makes two brands of antifreeze. The first brand is
55% pure antifreeze, and the second brand is 80% pure antifreeze. In order to obtain 170 gallons of a mixture that contains 60% pure antifreeze, how many gallons of each brand of antifreeze must be used?

Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
let x be the amount of 55% pure antifreeze and y be the amount of 80% pure antifreeze
:
1) x * 0.55 = 0.55x
:
2) y * 0.80 = 0.80y
:
3) 170 * 0.60 = 102
:
4) x + y = 170
:
Equation 3 is the mixture, we have
:
5) 0.55x + 0.80y = 102
:
solve equation 4 for x and substitute in equation 5
:
x = 170 - y
:
0.55(170-y) + 0.80y = 102
:
93.5 - 0.55y + 0.80y = 102
:
0.25y = 8.5
:
y = 34
:
x = 170 - 34 = 136
:
*****************************************************************************
We need 136 gallons of the 55% pure antifreeze and 34 gallons of the 80% pure antifreeze
*****************************************************************************
: