Question

I = $16 P = $200 T = 2 years

Answer 1

Next time, please include the instructions with your post.

The formula for simple interest is    i = p*r*t, where r is the annual interest rate expressed as a decimal fraction.

Here, $16 = $200*r*2, with r being the unknown.

Solving for r:    r = $16  /  $400   =  0.04  (answer)