Question

Alice Gleason invested a portion of 32000 at 9% interest and the balance at 11% interest how much did she invest at each rate if her total income from both investments was 3,200

Answer 1

Alice Gleason invested 16000 each for 9% and 11% rate respectively

Explanation:

Let

x = portion invested for 9%

y = portion invested for 11%

Then

x + y =32000 eqn(1)

0.09x + 0.11y =3200 eqn(2)

solving eqn(1) and eqn(2) simultaneously

multiply eqn(2) by 100 gives and eqn(1) by 9

9x +11y =320000 eqn(3)

9x + 9y = 288000 eqn(4)

subtract eqn(4) from eqn(3) to obtain y

2y = 32000

y=16000

substitute y=16000 into eqn(1) to obtain x

x=32000-16000

x=16000