Alice Gleason invested a portion of $32000 at 9% interest and the balance at 11% interest. How much did she invest each rate if her total income from both investments was $3200.

Respuesta :

Alice Gleason invested $ 16000 at 9 % interest and $ 16000 at 11 % interest

Solution:

Given, Alice Gleason invested a portion of $32000 at 9% interest and the balance at 11% interest.  

We have to find how much did she invest each rate if her total income from both investments was $3200.

Let the 1st part of amount be y, then second part will be $32000 – y.

[tex]\text { simple interest }=\frac{\text { pnr }}{100}[/tex]

Where "p" is principal amount

"n" is number of years

"r" is rate of interest

Now, according to given information,  

Simple interest for 1st part + simple interest for 2nd part = 3200

Considering to be for 1 year,

[tex]\begin{array}{l}{\frac{y \times 9 \times 1}{100}+\frac{(32000-y) \times 11  \times 1}{100}=3200} \\\\ {\frac{9y + 32000 \times 11-11 y}{100}=3200} \\\\ {320 \times 11-\frac{2 y}{100}=3200} \\\\ {\frac{y}{50}=3520-3200} \\\\ {y=50 \times 320=16000}\end{array}[/tex]

She invested $ 16000 at 9 % interest and $ 16000 at 11 % interest