Question 1207481
<br>
Here is a quick and easy non-algebraic method for solving any 2-part "mixture" problem like this.<br>
$10,000 all invested at 6% would yield $600 interest; all at 7% would yield $700 interest.<br>
Use any arithmetic method you want (perhaps a number line) to observe/calculate that $660 is 60/100 = 3/5 of the way from $600 to $700.<br>
That means 3/5 of the total was invested at the higher rate.<br>
3/5 of $10,000 is $6000.<br>
ANSWER: $6000 was invested at 7%, the other $4000 at 6%<br>
CHECK: .07($6000)+.06($4000) = $420+$240 = $660<br>