The mean score on the final exam in Ayanna's history class was 80.5 and the

standard deviation of the scores was 6.5. Ayanna's standard score, rounded to the

nearest tenth, was - 1.3. What was her score on the exam?

7 = r^1/2 is the same as saying 7 = square root of r. So, to get rid of the square root sign on the r, you need to square it, and when you do something to one side of the equation, you have to do the same to the other side. So after squaring both sides, you get 49 = r.