Question

You invested $9000 between two accounts paying 6% and 8% annual interest, respectively. If the total interest earned for the year was $640, how much was invested at each rate?

$____ was invested at 6% and $____ was invested at 8%.

Answer 1

x * .06 + (9000 -x) * .08 = 640
.06x -.08x + 720 = 640
-.02x = -80
x = 80 / .02
x = 4,000 (Amount that was invested at 6%)

So amount invested at 8% = 5,000