Question 696839
 an investor invest 2800 dollars into two mutual funds one has a profit of 5% the other has 2%, the total profit is 80, how much was invested in each fund. 
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Equations:
Quantity: a + b = 2800 dollars
Interest:5a + 2b = 8000
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Multiply thru the Quantity Equation by 2:
2a + 2b = 2*2800
5a + 2b = 8000
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Subtract and solve for "a":
3a = 2400
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s = 800 (amt. invested at 5%)
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Solve for "a":
a+b = 2800
a + 800 = 2800
a = 2000 (amt. invested at 2%)
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Cheers,
Stan H.