Question 58274
Mixture problems generally have several features in common, for example:
(1) They usually involve two or more substances
(2) They usually have an initial condition that, after some manipulation, results in a final condition.
(3) There usually exists more than one approach in solving the problems and
(4) Frequently, one of the substances does not change throughout the process and this is the first thing I look for!
This problem consists of a mixture of gold and, for lack of a better word, "otherstuff". We'll solve this problem using two approaches. NOTE: THE OTHERSTUFF DOES NOT CHANGE so lets look at the otherstuff first:

Let x=amount of pure gold added to the original 5 oz.
initial amt of otherstuff (5(.99))+amt of otherstuff added (x(0))=amt of otherstuff in final mixture ((x+5)(.94))
Thus, our equation is:
5(.99)=(x+5)(.94), or
.94x=.25;  x=.2659oz

Now lets look at the gold:

Amt of gold in the original 5 oz (5(.01))+amt of pure gold added (x(1))=amt of gold in final mixture ((x+5)(.06))
Thus, our equation is:
5(.01)+x=(x+5)(.06),or
.94x=.25; x=.2659oz

Hope this helps----ptaylor