SOLUTION: Mr.Caminiti has some money invested at 4% and three times as much invested at 6%.Her total annual income from the two investments is $ 1100.how muxh is invested at each rate?

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: Mr.Caminiti has some money invested at 4% and three times as much invested at 6%.Her total annual income from the two investments is $ 1100.how muxh is invested at each rate?      Log On


   



Question 1089741: Mr.Caminiti has some money invested at 4% and three times as much invested at 6%.Her total annual income from the two investments is $ 1100.how muxh is invested at each rate?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
(1) +I%5B1%5D+=+P%5B1%5D%2Ar%5B1%5D%2At+
(2) +I%5B2%5D+=+P%5B2%5D%2Ar%5B2%5D%2At+
----------------------
+I%5B2%5D+=+1100+-+I%5B1%5D+
+r%5B1%5D+=+.04+
+r%5B2%5D+=+.06+
+P%5B2%5D+=+3P%5B1%5D+
----------------------
(1) +I%5B1%5D+=+P%5B1%5D%2A.04%2A1+
(2) +1100+-+I%5B1%5D+=+3%2AP%5B1%5D%2A.06%2A1+
--------------------------------
(1) +I%5B1%5D+=+.04P%5B1%5D+
(2) +1100+-+I%5B1%5D+=+.18P%5B1%5D+
Plug (1) into (2)
(2) +1100+-+.04P%5B1%5D+=+.18P%5B1%5D+
(2) +.22P%5B1%5D+=+1100+
(2) +P%5B1%5D+=+5000+
and
+P%5B2%5D+=+3P%5B1%5D+
+P%5B2%5D+=+15000+
$5,000 invested @ 4%
$15,000 invested @ 6%
--------------------------
check:
(1) +I%5B1%5D+=+.04P%5B1%5D+
(1) +I%5B1%5D+=+.04%2A5000+
(1) +I%5B1%5D+=+200+
and
(2) +1100+-+I%5B1%5D+=+.18P%5B1%5D+
(2) +1100+-+I%5B1%5D+=+.18%2A5000+
(2) +1100+-+I%5B1%5D+=+900+
+P%5B1%5D+%2B+P%5B2%5D+=+200+%2B+900+
+P%5B1%5D+%2B+P%5B2%5D+=+1100+
OK