SOLUTION: Sam needs 3 lb of metal with 43% silver. If sam combines one metal with 18% silver, and another with 80% silvet, how much metal does he need?

Question 991979: Sam needs 3 lb of metal with 43% silver. If sam combines one metal with 18% silver, and another with 80% silvet, how much metal does he need?
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Let = pounds of 18% silver needed
Let = pounds of 80% silver needed
-----------------
(1)
(2)
---------------------------
(2)
(2)
Multiply both sides of (1) by
and subtract (1) from (2)
(2)
(1)
----------------------

and
(1)
(1)
1.79 pounds of 18% silver are needed
1.21 pounds of 80% silver are needed
-------------------------------
check:
(2)
(2)
(2)
(2)
OK
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