A firm recommends a client invest in bonds rated AAA, A and B. The average yield on AAA bonds is 4%, on A bonds 5% and on B bonds 8%. The client wants to invest twice as much in AAA bonds as in B binds. How much should be invested in each type of bond if the total investment is $21,000 and the investor wants an annual return of $1100 on the three investments?

$10,000 in AAA Bonds

$6,000 in A bonds

$5,000 in B bonds

Can you explain solution clearly