SOLUTION: Rachel invested $9000 in money market funds, part at 6% and the rest at 4.5% annual interest. after one year, she earned $ 480.75 in interest. How much was invested at each rate?

Question 1151867: Rachel invested $9000 in money market funds, part at 6% and the rest at 4.5% annual interest. after one year, she earned $ 480.75 in interest. How much was invested at each rate?
Answer by ikleyn(52776) (Show Source): You can put this solution on YOUR website!
.


x dollars invested at 6% and the rest, (9000-x) dollars invested at 4.5%.


The total interest is the sum of partial interest.


In the equation form it is


    0.06x + 0.045*(9000-x) = 480.75  dollars.


From the equation,  


    x =  = 5050  dollars.


ANSWER.  $5050 invested at 6%  and the rest,  9000-5050 = 3950  dollars invested at 4.5%.


CHECK.   0.06*5050 + 0.045*3950 = 480.75 dollars.   ! Precisely correct !

Solved.

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