<PRE><B>Question 1171078</B>
&lt;br&gt;
A setup for a formal algebraic solution....&lt;br&gt;
x = amount invested at 8.5%
22000-x = amount invested at 4%&lt;br&gt;
The total interest was $1510:&lt;br&gt;
{{{.085(x)+.04(22000-x) = 1510}}}&lt;br&gt;
Solve using basic algebra... though the decimals make the calculations a bit unpleasant.&lt;br&gt;
I leave it to you to finish the problem by that path.&lt;br&gt;
Here is a method that gets you to the answer with what I think is far less effort....&lt;br&gt;
(1) $22000 all invested at 8.5% would yield $1870 interest; all at 4% would yield $880 interest.
(2) Look at the three interest amounts on a number line -- 880, 1510, and 1870 -- and determine with simple calculations that $1510 is 630/990 = 7/11 of the way from $880 to $1870.
(3) That means 7/11 of the total was invested at the higher rate.&lt;br&gt;
ANSWER: 7/11 of $22,000, or $14,000, was invested at 8.5%; the other $8000 at 4%.&lt;br&gt;
CHECK: .085(14000)+.04(8000) = 1190+320 = 1510&lt;br&gt;
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