SOLUTION: A man invests $5500 dollars in three accounts that pay 5%, 8%, and 9% in annual interest respectively. He has two times as much money invested at 9% as he does at 8%. If the total

Algebra ->  Customizable Word Problem Solvers  -> Finance -> SOLUTION: A man invests $5500 dollars in three accounts that pay 5%, 8%, and 9% in annual interest respectively. He has two times as much money invested at 9% as he does at 8%. If the total       Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


   



Question 672425: A man invests $5500 dollars in three accounts that pay 5%, 8%, and 9% in annual interest respectively. He has two times as much money invested at 9% as he does at 8%. If the total interest earned for the year is $449, how much is invested at 5%?
Found 2 solutions by josmiceli, mananth:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +x+ = amount invested @ 8%
+2x+ = amount invested @ 9%
Let +y+ = amount invested @ 5%
--------------
(1) +x+%2B+2x+%2B+y+=+5500+
(2) +.08x+%2B+.09%2A%282x%29+%2B+.05y+=+449+
--------------
(1) +3x+%2B+y+=+5500+
(1) +y+=+5500+-+3x+
and
(2) +.08x+%2B+.18x+%2B+.05y+=+449+
(2) +.08x+%2B+.18x+%2B+.05%2A%28+5500+-+3x+%29+=+449+
(2) +.26x+%2B+275+-+.15x+=+449+
(2) +.11x+=+449+-+275+
(2) +.11x+=+174+
(2) +x+=+1581.82+
and
(1) +y+=+5500+-+3x+
(1) +y+=+5500+-+3%2A1581.82+
(2) +y+=+5500+-+4745.45+
(2) +y+=+754.55+
$754.55 was invested @ 5%
check:
+x+=+1581.82+
+2x+=+3163.64
+1581.82+%2B+3163.64+%2B+754.55+=+5500+
+5500.01+=+5500+
close enough
(2) +.08x+%2B+.09%2A%282x%29+%2B+.05y+=+449+
(2) +.08%2A1581.82+%2B+.09%2A3163.64%2B+.05%2A754.55+=+449+
(2) +126.55+%2B+284.73+%2B+37.73+=+449+
(2) +449.01+=+449+
close enough





Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
8%-------------------x
9%-------------------2x
Balance @
5%-------------------(5500-3x)
Interest = 449
0.08x+0.09(2x)+0.05(5500-3x)=449
Multiply by 100
8x+18x+27500-15x=44900
11x=44900-27500
11x=17400
x= 1581.82................8%
2x=3163.64.................9%
754.55.....................5%