SOLUTION: Sam earned $42,000 in selling antiques. He invested part at 15% simple interest and the rest at 12%, earning $5790 per year in interest. How much did he invest at each rate?

Question 147626: Sam earned $42,000 in selling antiques. He invested part at 15% simple interest and the rest at 12%, earning $5790 per year in interest. How much did he invest at each rate?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Sam earned $42,000 in selling antiques. He invested part at 15% simple interest and the rest at 12%, earning $5790 per year in interest. How much did he invest at each rate?
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EQUATIONS:
x + y = 42000
0.15x + 0.12y = 5790
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Rearrange:
15x + 12y = 579000
12x + 12y = 12*42000
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3x = 75000
x = $25000 (amount invested at 15%)
y = 42000-25000 = $17,000 (amount invested at 12%)
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Cheers,
Stan H.

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