<PRE><B>Question 1170431</B>
&lt;br&gt;
Given the ratio 4:9:2, let the amounts of the three metals be
tin: 4x
iron: 9x
nickel: 2x&lt;br&gt;
The amount of tin has to be at most 200g:
4x &lt;= 200
x &lt;= 50&lt;br&gt;
The amount of iron has to be at most 500g:
9x &lt;= 500
x &lt;= 55 5/9&lt;br&gt;
The amount of nickel has to be at most 90g:
2x &lt;= 90
x &lt;= 45&lt;br&gt;
The nickel is the most restrictive; the maximum value of x is 45.&lt;br&gt;
The maximum amount of alloy you can make is 4x+9x+2x = 15x = 15*45g = 675g.&lt;br&gt;
ANSWER: 675 grams&lt;br&gt;
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