SOLUTION: I made a big typo with my last question... "The owner of a deli mixed coffee that cost $9/lbwith coffee that cost $6/lb. How many lbs of each were used to make a 20lb mixture c

Algebra ->  Customizable Word Problem Solvers  -> Mixtures -> SOLUTION: I made a big typo with my last question... "The owner of a deli mixed coffee that cost $9/lbwith coffee that cost $6/lb. How many lbs of each were used to make a 20lb mixture c      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 757645: I made a big typo with my last question...
"The owner of a deli mixed coffee that cost $9/lbwith coffee that cost $6/lb. How many lbs of each were used to make a 20lb mixture costing $7.80/lb."
Answer by htmentor(1343) About Me  (Show Source):
You can put this solution on YOUR website!
Let a = the number of lbs of the $9/lb coffee
Since there are 20 lbs in the mixture, the number of lbs of the $6/lb coffee will be 20 - a
Adding up the total dollar amount of the two coffees and equating that to the total in the mixture gives
9a + 6(20-a) = 7.80*20
Solve for a:
9a + 120 - 6a = 156
3a = 36
a = 12
So there are 12 lbs of the $9 coffee and 8 lbs of the $6 coffee