an investment of $50,000 was made by a busines 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 $3960. the interest from the first investment was two time the interest from the second. find the amounts of the three parts of the investment.

1 answer

first part --- x
2nd part --- y
3rd part ---- 50000-x-y

interest on 1st = .08x
interest on 2nd = .06y
3rd interest = .09(50000-x-y)

but .08x = 2(.06)y
8x = 12y
y = 8x/12 = 4x/3

.08x + .06y + .09(50000-x-y) = 3960
sub in y = 4x/3 and solve

I am sure you can take it from here