SOLUTION: Dr. Beaker invested $3000, part at 8% and the rest at 7 1/2%. The total return for one year was $231. How much was invested at each rate?

Algebra ->  Customizable Word Problem Solvers  -> Finance -> SOLUTION: Dr. Beaker invested $3000, part at 8% and the rest at 7 1/2%. The total return for one year was $231. How much was invested at each rate?      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 160305: Dr. Beaker invested $3000, part at 8% and the rest at 7 1/2%. The total return for one year was $231. How much was invested at each rate?
Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!

Let's supposed "x" is invested @ 8% and the rest ---> "$3000-x" is invested @ 7.5% that has a return of $231 in 1 year. Putting into eqn:
0.08x%2B0.075%283000-x%29=231 , WORKING EQN
0.08x%2B225=0.075x=231
0.005x=231-225=6
cross%280.005%29x%2Fcross%280.005%29=cross%286%291200%2Fcross%280.005%29
x=1200, amount invested at 8%.
3000-1200=1800 amount invested at 7.5%
Let's check, go back WORKING EQN:
0.08%281200%29%2B0.075%281800%29=231
96%2B135=231
231=231
Thank you,
Jojo