<PRE><B>Question 99518</B>
Set up three equations.
Let the three alloys by a, b, c
1st equation: Copper---: 0.7a+.6b+.3c = 0.50(1000)=500  mg
2nd equation: Zinc-----: 0.2a+ 0b+.4c = 0.18(1000)=180 mg
3rd equation: Nickel---:..............= 0.32(1000)=320 mg
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This is three equations in three unknows.
I used the Matrix method on a TI calculator and found
a = 140 mg of the 1st alloy
b = 480 mg of the 2nd alloy
c = 380 mg of the 3rd alloy
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cheers,
Stan H.
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