Question 77991
Melinda Bowen recieves an annual income of $234.50 from investing one amount of money at 6% and another amount at 5%. If the investments were interchanged, her income would increase by$5.10. Find the amounts she invested. 
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Let amount invested at 6% be x Interest on this is 0.06x
Let amount invested at 5% be y Interest on this is 0.05y
EQUATION:
0.06x+0.05y=234.50
Interchanging the investment you get:
0.05x+0.06y=234.50+5.10=239.60
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Rewriting the equations you get:
6x+5y=23450
5x+6y=23960
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Multiply the 1st equation thru by 5 and the 2nd equation thru by 6 to get:
30x+25y=117250
30x+36y=143760
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Subtract the 1st from the 2nd and solve for "y":
11y=26510
y=$2410
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Substitute to be able to solve for "x":
6x+5(2410)=23450
6x+12050=23450
6x=11400
x=$1900
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Cheers,
Stan H.