An investor has $300,000 to invest. If part is invested at 5% & the rest at 9%, how much should be invested...?

Hye Caulley: Here's how you solve this:Let X = the amount invested at 5%.So (300,000 - X) = the amount invested at 9%.Then you solve for:.05X + .09(300,000 - X) = 300,000 x .08, this reduces down to.05X + 27,000 - .09X = 24,000, which further reduces to3,000 = .04X, which finally reduces toX = 75,000, which is the amount invested at 5%.So 300,000 - 75,000 = 225,000 is the amount invested at 9%You can prove these numbers by calculating the following:75,000 X 5% = 3,750225,000 X 9% = 20,2503,750 + 20,250 = 24,000, and 24,000 / 300,000 = 8%, and you've proved your answer...Show more