Problema Solution
the computer club invested 2200 dollars, part at 4.5% interest and the rest at 7%. The total annual interest earned was $144. how much was invested at each rate?
Answer provided by our tutors
let x="amount @ 4.5%", so 2200-x="amount @ 7%"
So,
.045x+.07(2200-x)=144
.045x+154-.07x=144
-.025x=-10
x=$400 at 4.5%
$1800 at 7%