A total of $32000 is invested in two municipal bonds that pay 5.75% and 6.25% simiple interest. The investor wants an annual interest income of $1900 from the investments. What amount should be invested in the 5.75% bond?

Answer 1

If the amount of money he invested at the 2muinicipal bond that pays 5.75% and 6.25% are m&n

Then

M+N=32000.....(*)

5.75%ofm and 6.25%of n

When you add them it must give him an interest of $1900

575m/10000+625n/10000=1900

575m+625n=19000000

Reduce by 25

23m+25n=760000.....(**)

You goal is to get m

So from (*)

N=32000-m

Plug "N" into (**)

23m+25(32000-m)=760000

23m+800000-25m=760000

-2m=760000-800000

-2m=-40000
m=$20000