Joan Arlington has twice as much money invested at 5% simple annual interest as she does at 4%. If her yearly income does she have at each rate?

Question

At 4%, she has
At 5%, she has

Answer 1

$Po @ 4%.
$2Po @ 5%.

Po*0.04*1 + 2Po*0.05*1 = $378.
.04Po + .10Po = 378
0.14Po = 378
Po = $2700. @ 4%.
Int. = 0.04*2700 = $108.

2Po = $5400 @ 5%.
Int. = 0.05*5400 = $270.