Principal Income is
.
Rate of interest
.
The invested amount is 
Find the time period when compounded monthly.
\
.
For monthly compounded
.
Substitute all the values in the equation.
\







The time period is
years.
Find the time period when compounded continuously.
\
Sunstitute
,
and
in the above equation.





The time period is
years.
years and
years.