Meisha has $25,000 that she wants to invest. She invests it in accounts paying 12%, 7%, and
6% simple interest. The account paying 12% is a higher-risk account, so she wants the
amount in that account to be half of the amount she has in the account paying 6% simple
interest. If her annual interest is $1945, how much is invested at each rate?
Let amount invested at 12% be S, and the amount invested at 7%, A
Then amount invested at 6% is 2S
We then get: S + A + 2S = 25,000______3S + A = 25,000 -------- eq (i)
Also, .06(2S) + .07A + .12S = 1,945______.12S + .07A + .12S = 1,945_____.24S + .07A = 1,945 ------- eq (ii)
Solve this system to get S, or amount invested @ 12%, which is $6,500
Figure out the rest!!