SOLUTION: a man has 100,000 part of which he invest at 12% interest and the rest at 18%. He received a total annual interest of 15,300. how much did he invest at each rate?

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Question 1032885: a man has 100,000 part of which he invest at 12% interest and the rest at 18%. He received a total annual interest of 15,300. how much did he invest at each rate?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
a man has 100,000 part of which he invest at 12% interest and the rest at 18%. He received a total annual interest of 15,300. how much did he invest at each rate?
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Quantity Eq:: t + e = 100,000
Interest Eq:: 12t + 18e = 1530000
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Modify for elimination::
12t + 12e = 1200000
12t + 18e = 1530000
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Subtract and solve for "e":
330000 = 6e
e = $55,000 (amt. invested at 18%)
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The rest was invested at 12%.
Cheers,
Stan H.
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