SOLUTION: Solve: 17-4x/12=5 An 80-pound grass seed mixture is 30% bluegrass seed. How many pounds of seed containing no bluegrass seed (0%) should be added to the seed mixture

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: Solve: 17-4x/12=5 An 80-pound grass seed mixture is 30% bluegrass seed. How many pounds of seed containing no bluegrass seed (0%) should be added to the seed mixture      Log On


   

Question 60648: Solve: 17-4x/12=5





An 80-pound grass seed mixture is 30% bluegrass seed. How many pounds of seed containing no bluegrass seed (0%) should be added to the seed mixture for a resulting blend that is 20% bluegrass seed?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!

Solve%3A+17-4x%2F12=5
:
Get rid of the denominator, mult eq by 12, results:
12(17) - 4x = 12(5)
:
204 - 4x = 60
-4x = 60 - 204
-4x = -144
:
Divide both sides by -4
x = -144/-4
x = 36
:
:
An 80-pound grass seed mixture is 30% bluegrass seed. How many pounds of seed containing no bluegrass seed (0%) should be added to the seed mixture for a resulting blend that is 20% bluegrass seed?
:
Let x = amt of of "no bluegrass" seed
:
Write a per cent blue grass equation:
.30(80) + 0(x) = .20(80+x)
:
24 + 0 = 16 + .2x
24 - 16 = .2x
8 = .2x
x = 8/.2
x = 40 lb of "no bluegrass" seed