janet karrenbrock deposits some money at 2.5% interest, with twice as much deposited at 3%. find the amount deposited at each rate if the total annual interest income is $850

Question

This is a question on a homework assignment that I can't figure out. I'm not sure how to set up the equation

Answer 1

janet karrenbrock deposits some money at 2.5% interest, with twice as much deposited at 3%. find the amount deposited at each rate if the total annual interest income is $850

X = the amount of money deposited

Y = total amount of interest

(0.025*x) + (0.03*(2x)) = Y

(0.025*x) + (0.03*(2x)) = 850

solve for X

0.025x + 0.06x = 850

0.085x = 850

x = 850/0.085

x = $10,000

So, she deposited $10,000 at 2.5% (X) and $20,000 at 3% (2X).