Lisa Chen invested $24,000, part at 8% and the rest at 7.2%. How much did she invest at each rate if her income from the 8% investment is two thirds that of the 7.2% investment?
Because the two interest rates are slightly different,the investment
at 8% will be less than 2/3 of the
7.2% investment by an amount equal
to the difference between the interest
rates. 2/3=0.6666, 0.6666-(.08-.072)=
0.6586. The investment at 7.2%=X dollars, The investment at 8%=0.6586X
dollars. X+0.6586X=24000, X=14470.03
0.6586X=9529.96
INV @ 7.2%=14,470.03
INV @ 8%=9529.96