Question

$500, 12%,18 months HELP!!!!!!!!!!

Answer 1

If I assume that you merely want the simple interest, then:

i = $500 (0.12) (3/2) = 90 dollars simple interest was earned.


If you want the accrued amount, with compounding twice yearly, then

A = $500 (1+0.12/2)^3 = $595.51.  In this case the interest earned is $95.51.