# Annual and daily growth rate

1. Oct 28, 2004

### vt33

Hello, my problem is:

Let Q(t) = 8(0.87)^t

Find the annual and daily growth rate.
Can anyone tell me how to set this up? I don't want you to show me the whole problem, just the 1st step. Thanks a ton!!!

2. Oct 28, 2004

### vsage

what units does t have? years?

3. Oct 29, 2004

### vt33

units

t=months in the equation

4. Oct 29, 2004

### vsage

Ok so how many t in a year? How many t in a day? Just sub those relationships back into the equation and you got your answers.

5. Oct 29, 2004

### vt33

????

OK, this is what I tried. 8(0.87)^12 and I get 1.50425. I also tried 8(0.87)^(1/12) and I get 7.46. I also tried using 0.13 in replace of 0.87. As you can see, I have tried everything I can think of and tried to manipulate this all I can. Am I using the right numbers? Or, am I setting up the equation incorrectly?

6. Oct 29, 2004

### vsage

Think about how to convert months to years. t months * 1 year/12 months = t years. I hope I didn't lose you when I multiplied by that constant. I'm saying your second formula is right.