Help with an investment matrix word problem

[kdubb22]

Help with an investment matrix word problem!

Can anyone give me the 3 equations in general form that I need to solve this matrix?

A person will put 30% of his investment into a stock fund that earns a 9% annual rate of return. He will put 20% in precious metals currently growing at 40% and the remainder into bond funds earning 3%. His goal is to have $4000 of interest income. How much should he put into each investment?

One of the equations should be the equation for the statement about interest.

 

[gsal]

I don't think this is a matrix kind of problem...it is a single equation:

(0.3xM)x(1.09) + (0.2xM)x(1.40) + (0.5xM)x(1.03) - M = 4000

M is the amount of money that needs to be invested to get 4000 of interest income

 

[pmsrw3]

Can anyone give me the 3 equations in general form that I need to solve this matrix?

A person will put 30% of his investment into a stock fund that earns a 9% annual rate of return. He will put 20% in precious metals currently growing at 40% and the remainder into bond funds earning 3%. His goal is to have $4000 of interest income. How much should he put into each investment?

One of the equations should be the equation for the statement about interest.

Do you really mean interest should be $4000, or total return? The reason I ask is that only the bonds return interest.