Question

Larry mitchell invested part of his 14,000 advance at 7% annual simple interest and the rest at 9% annual simple interest. If his total yearly interest from both account was $1,140 find the amount invested each rate.

Answer 1

$6000 at 7%; $8000 at 9%

Explanation:

total amount = 14,000

let x = amount invested at 7%

let y = amount invested at 9%

total interest = 1140

I = Prt

1140 = 0.07x + 0.09y

x + y = 14000

y = 14000 - x

1140 = 0.07x + 0.09(14000 - x)

1140 = 0.07x + 1260 - 0.09x

-120 = -0.02x

x = 6000

x + y = 14000

y = 8000

$6000 at 7%; $8000 at 9%