Question 1164248
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(1) A typical formal algebraic setup for solving the problem:<br>
x amount at 3%, plus ($5000-x) amount at 7%, yields $190 interest.<br>
{{{.03(x)+.07(5000-x) = 190}}}<br>
Solve using basic algebra; I leave that to you.<br>
(2) A quick and easy way to solve any two-part "mixture" problem like this, if a formal algebraic solution is not required:<br>
$5000 all invested at 3% would yield $150 interest; all at 7$ would yield $350 interest.
The actual interest, $190, is 40/200 = 1/5 of the way from $150 to $350.  (If it helps, picture the three dollar amounts 150, 190, and 350 on a number line; 150 to 190 is a difference of 40, 150 to 350 is a difference of 200, so 190 is 40/200 = 1/5 of the distance from 150 to 350.)
That means 1/5 of the total was invested at the higher rate.<br>
ANSWER: 1/5 of the $5000, or $1000, at 7%; the other $4000 at 3%.<br>
CHECK: .03(4000)+.07(1000) = 120+70 = 190<br>