An investor has $300,000 to invest in two types of investments. Type A pays 4% annually and type B pays 5% annually. To have a well-balanced portfolio, the investor imposes the following conditions. At least one-third of the total portfolio is to be allocated to type A investments and at least one-third of the portfolio is to be allocated to type B investments. What is the optimal amount that should be invested in each investment?

I need to somehow graph it as well. I've been working on it for a couple days and I can't even come up with the equations.

Question

An investor has $300,000 to invest in two types of investments. Type A pays 4% annually and type B pays 5% annually. To have a well-balanced portfolio, the investor imposes the following conditions. At least one-third of the total portfolio is to be allocated to type A investments and at least one-third of the portfolio is to be allocated to type B investments. What is the optimal amount that should be invested in each investment?

I need to somehow graph it as well. I've been working on it for a couple days and I can't even come up with the equations.