SOLUTION: The question from the text book is this "Bill invested three times as much money at 9% as at 7.5%. If he wanted his interest at the end of the year to be $1725, what amount of mone

Algebra ->  Algebra  -> Percentages: Solvers, Trainers, Word Problems and pie charts -> SOLUTION: The question from the text book is this "Bill invested three times as much money at 9% as at 7.5%. If he wanted his interest at the end of the year to be $1725, what amount of mone      Log On

Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations!
Ad: Algebra Solved!™: algebra software solves algebra homework problems with step-by-step help!

   

Question 208811: The question from the text book is this "Bill invested three times as much money at 9% as at 7.5%. If he wanted his interest at the end of the year to be $1725, what amount of money should he inves a 7.5%?"
Answer by ankor@dixie-net.com(12692) About Me  (Show Source):
You can put this solution on YOUR website!
"Bill invested three times as much money at 9% as at 7.5%.
If he wanted his interest at the end of the year to be $1725,
what amount of money should he invest a 7.5%?"
;
Let x = amt invested at 7.5%
then "three times as much money at 9% as at 7.5%" therefore:
3x = amt invested at 9%
;
Write the interest equation:
.09(3x) + .075x = 1725
.27x + .075x = 1725
.345x = 1725
x = 1725%2F.345
x = $5000 invested at 7.5%
:
:
Check solution (15000 invested at 9%)
.09(15000) + .075(5000) =
1350 + 375 = 1725