# percent annual growh rate

• Oct 13th 2008, 10:17 PM
Kate182
percent annual growh rate
How do i find the percent annual growth or decay rate and the continuaous percent growht or decay rate per year with this formula:

y=100(0.9324)^t
• Oct 14th 2008, 12:25 AM
Prove It
Quote:

Originally Posted by Kate182
How do i find the percent annual growth or decay rate and the continuaous percent growht or decay rate per year with this formula:

y=100(0.9324)^t

Use logarithms.

$\log_{10}{y} = \log_{10}{100(0.9324)^t}$

$\log_{10}{y} = \log_{10}{100} + \log_{10}{(0.9324)^t}$

$\log_{10}{y} = 2 + t\log_{10}{0.9324}$

$\log_{10}{y} - 2 = t\log_{10}{0.9324}$

$t = \frac{\log_{10}{y} - 2}{\log_{10}{0.9324}}$.