Drexel dragonThe Math ForumDonate to the Math Forum



Search All of the Math Forum:

Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.


Math Forum » Discussions » Math Topics » alt.algebra.help.independent

Topic: I need help setting up this system of equations
Replies: 1   Last Post: Nov 26, 2008 7:37 AM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
dash

Posts: 1
From: nc
Registered: 11/25/08
I need help setting up this system of equations
Posted: Nov 25, 2008 2:22 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

I'm trying to set up a system of three equations. I have two of them, but I can't get the third. Anyone know what to do? Here's the problem:

Jane's employer gave her a bonus of $1600. She decided to invest all the money, some at 5%, some at 7%, and some at 8%. She invested three times more money at 8% than she did at 5%. At the end of one year the total interest she earned was $115.


Here are the first two equations of the system I've found:

x + y + z = 1600
.05 x + .07y + .08z = 115

I'm stumped as to what the third one is. I need the third one to solve and figure out how much money this bitch invested in each. Can anyone help? Thanks in advance.



Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© Drexel University 1994-2014. All Rights Reserved.
The Math Forum is a research and educational enterprise of the Drexel University School of Education.