word problem

Question

A woman has a total of $14,000
to invest. She invests part of the money in an account that pays
7%
per year and the rest in an account that pays 9%
per year. If the interest earned in the first year is $1160
, how much did she invest in each account?

Answer 1

I = Prt

Interest = principal*rate*time

 

The total interest will earned, 1160, is equal to the sum of

the interest earned at each rate.

 

If we invest $x at 7% then we invest 14000-x at 9%

 

1160 = x(.07)(1) + (14000-x)(.09)(1)

1160 = .07x + 1260 - .09x

-100 = -.02x

 

x = -100/(-.02) = $5,000 invested at 7%

14000-x = $9,000 invested at 9%