word problem
posted by XOCHIL on .
An investment of $93,000 was made by a business club. the investment was split into three parts and lasted for one year. The first part of the investment earned 8% interest, the second earned 6% and the third 9%. total interest from the investments was $7110. The interest from the first investment was 3 times the interest from the second. Find the amounts of the three parts of th investment??

second part  x
first part  3x
third part  (93000  x  3x) = 93000  4x
.08(3x) + .06x + .09(930004x) = 7110
.24x + .06x + 8370  .36x = 7110
.06x = 1260
x = 1260/.06 = 21000
second investment = x = $21000
first investment = 3x = $63000
third investment = 930004x = $9000
check:
63000(.08) + 21000(.06) + 9000(.09) = 7110 
for twenty years