$5400 is invested how much is invested at 10% and 7%

Question

$5400 was invested. Part of it at 10% and part of it at 7%. For a certain year, the total yield is $468.00.

 How much was invested at each rate? Must show all work.

Answer 1

me thank yu tri tu sae yu hav 5400$

& yu get INTEREST on it...sum at 7% & sum at 10%

total interest for 1 yeer=468$

so 7%*x+10%*y=468$

x+y=5,400$, so y=5400-x

0.1*x+0.07*(5400-x)=468

0.1x -0.07x +378=468

0.03x=468-378=90

x=90/0.03=3,000

y=5400-3000=2,400

Answer 2

Let Quantity Equation: x + y = 5400 dollars

Interest Equation:0.10x + 0.07y = 469 dollars

Multiply thru 1st by 10
Multiply thru 2nd by 100
10x + 10y = 54000
10x + 7y = 46900

Subtract and solve for "y"
3y = 7100
y = $2366.67 (amt. invested at 7%)

Solve for "x"
x+ y = 5400
x = 5400-2366.67
x = $2633.33 (amt. invested at 10%)

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