Question

What is the annual interest rate if $1600 is invested for 6 years and $456 in interest is earned

Answer 1

Use the formula   i = p*r*t:
                                                               $456
$456 = $1600*r*6.  Solving for r, r = ----------------- = 0.0475, or 4 3/4%
                                                           ($1600)(6)