Phillip R. answered • 09/14/14

Tutor

New to Wyzant
Top Notch Math and Science Tutoring from Brown Univ Grad

let x = total amount invested

interest from each investment = amount x rate

The total interest = $6550

25%x(4%) + 40%x(6%) + 35%x(9%) = 6550 now solve for x

.25x(.04) + .40x(.06) + .35x(.09) = 6550

25x(4) + 40x(6) + 35x(9) = 6550 x 100 x 100

100x + 240x + 315x = 65,500,000

655x = 65,500,000

x = $100,000 is total amount invested