Question

You invest $6000 in two account paying 6% and 9% annual interest. At the end of the year, the account earn the same interest. How much was invest at each rate?

Answer 1

P(1+.06) = P(1+.09) solve

Answer 2

x + y = 6000
.06x = .09y

Answer 3

x + y = 6000
.06x - .09y = 0 (multiply by 100)

Answer 4

x + y = 6000
6x - 9y = 0

Answer 5

9(x + y = 6000)
6x - 9y = 0

9x + 9y = 54000
6x - 9y = 0

Answer 6

15x = 54000
x = 3600

Answer 7

y = 2400

Answer 8

So $3600 at 6% and $2400 at 9%

Answer 9

(Thanks, blexting and indy25, I also have another problem) The manager of a Starbuck store plans to mix A-grade coffee that cost $9.50per pound with B-grade coffee that costs $7.00per pound to create a 20-pound blend that will sell for $8.50 per pound. How many pounds of each type of coffee are required?

Answer 10

lol, I would put in 20 lbs of $7/pound