<PRE><B>Question 248666</B>
Anne and Nancy use a metal alloy that is a 24.9% copper to make jewelry.
 How many ounces of 20% alloy must be mixed with a 27% alloy to form 100 ounces of the desired alloy?
:
Let x = amt of 20% alloy
then
(100 - x) = amt of 27% alloy
:
.20x + .27(100-x) = .249(100)
:
.20x + 27 - .27x = 24.9
:
.20x - .27x = 24.9 - 27
:
-.07x = -2.1
x = {{{(-2.1)/(-.07)}}}
x = 30 oz of 20% alloy required
;
;
Check solution:
.20(30) + .27(70) = 
6 + 18.9 = 24.9</PRE>