Question 896479
An investor wants to mix a 1% investment and a 3.1% investment to create a portfolio with a 1.8% profit.
 What percentage of the portfolio must be invested in the first and second investment respectively?
:
let's use a total value of $1000 for the two investments.
let x = amt invested at 3.1%
then
(1000-x) = amt invested at 1%
:
.01(1000-x) + .031x = .018(1000)
10 - .01x + .031x = 18
-.01x + .031x = 18 - 10
.021x = 8
x = {{{8/.021}}}
x = 380.95 invested at 3.1%; which is 381/1000 = 38.1%
then
1000 - 381 = $619 invested at 1%, which is 619/1000 = 61.9%