how did you get rid of the 10 root ? can you show me how did we get 0.03352

Example 1: You are given that the CPI was 96.0 in 1985 and 133.5 in 1995 . What was the average annual compound rate of inflation (r) over this time period? Solution: 133.5=96(1+r)10 or (133.5/96)=(1+r)10 where r= inflation rate and solving gives r=0.03352 or r3.35%