SOLUTION: A printer has ink that is 3% cobalt blue color and ink that is 27% cobalt blue color. How many ounces of each ink are needed to make 3 gallons (384 ounces) of ink that is 15% cobal

Algebra ->  Customizable Word Problem Solvers  -> Finance -> SOLUTION: A printer has ink that is 3% cobalt blue color and ink that is 27% cobalt blue color. How many ounces of each ink are needed to make 3 gallons (384 ounces) of ink that is 15% cobal      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 1126233: A printer has ink that is 3% cobalt blue color and ink that is 27% cobalt blue color. How many ounces of each ink are needed to make 3 gallons (384 ounces) of ink that is 15% cobalt blue color?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a+ = ounces of 3% c.b. ink
Let +b+ = ounces of 275 c.b ink
----------------------------------------
(1) +a+%2B+b+=+384+
(2) +%28+.03a+%2B+.27b+%29%2F+384+=+.15+
---------------------------------------
Multiply both sides of (1) by 3
and subtract from (2)
(2) +.03a+%2B+.27b+=+57.6+
(2) +3a+%2B+27b+=+5760+
(1) +-3a+-+3b+=+-1152+
-------------------------------
+24b+=+4608+
+b+=+192+
and
(1) +a+%2B+192+=+384+
(1) +a+=+192+
----------------------------
192 ounces of each are needed
check:
(2) +.03%2A192+%2B+.27%2A192+=+57.6+
(2) +192%2A.3+=+57.6+
(2) +57.6+=+57.6+
OK