An investment of $53,000 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 6%, and the third 9%. Total interest from the investments was $4050. The interest from the first investment was 4 times the interest from the second. Find the amounts of the three

1 answer

.08 a + .06 b + .09 c = 4050
a + b + c = 53,000
.08 a = 4 * .06b
================
a = .24 b / .08 = 3 b
so
4 b + c = 53,000
c = 53,000 - 4 b
so
.08 a + .06 b + .09 c = 4050
is now
.08 (3b) + .06 b + .09 (53,000 -4b) = 4050
solve for b and go back for a and c