Question 1204124
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Here is an informal solution method that can be used for any 2-part "mixture" problem like this.<br>
All $18,050 earning 10% would yield interest of $1805; all earning 12% would yield  $2166.<br>
Use a number line or any similar method to find that the actual interest of $2041 is 236/361 of the way from $1805 to $2166.<br>
That means 236/361 of the total earned the higher interest rate.<br>
(236/361)($18050) = 236($500) = $11800<br>
ANSWERS: $11,800  was invested in the fund that earned 12% interest; the other $6250 was invested in the fund that earned 10% interest.<br>
CHECK: .10($6250)+.12($11800) = $625+$1416 = $2041<br>
Because of the "ugly" numbers in this problem, this informal method is not much faster than the standard formal algebraic solution method.  But when the numbers are "nice", this method can be MUCH faster if your mental arithmetic is good.<br>