how long will it take money to triple itself at 9.5% compound interest and 9.5% simple interest respectively?

Let n = number of years required:

Compound interest:
3P=P(1.095)^n
Solve for n:
3=1.095^n
take log on both sides:
n log(1.095)=log(3)
n = log(3)/log(1.095)

Simple interest:
3P=P(1+0.095*n)
Solve for n:
n=(3-1)/0.095 = 2/0.095