An alloy weighing 18 ounces is 70 percent gold. How many ounces of pure gold must be added to create an alloy that is 90 percent gold?
Choose the correct choice from the following answers:	A) 6	B) 90	C) 12	D) 24	E) 48
In 24 ounces, gold is 18 * (70/100)= 
<gadget id="calculator">18 * (70/100)</gadget>
<output>63/5 = around 12.6</output>
12.6 ounces. Now we add x ounces of pure gold to make it 90% gold.   So 12.6 + x= (24 + x)* 90/100 =&gt; x =90.   Answer is 90.
<result>B</result>
An alloy weighing 18 ounces is 70 percent gold. How many ounces of pure gold must be added to create an alloy that is 90 percent gold?