Question 1167134
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Algebraically, 4% of amount x, plus 5% of amount (9000-x), is 405:<br>
{{{.04(x)+.05(9000-x) = 405}}}<br>
Solve using basic algebra.<br>
A quick non-algebraic path to the answer is to calculate that $405 interest on $9000 is 4.5%; since that is exactly halfway between 4% and 5%, the money must have been invested half at each rate.<br>
ANSWER: $4500 at each rate<br>
CHECK: .04(4500)+.05(4500) = 180+225 = 405<br>