1. ## Average price

Hi I am having a hard time figuring out how to finish off this problem any help would be great thanks.

Otis taylor plots the price per share of a stock that he owns as a function of time and finds that it can be approximated by the function.

S(t) =t(25-5t)+18

Where t is the time (in years) since the stock was purchased. Find the average price of the stock over the first five years.

I have started the problem according to my book and I am stuck here is where I have gotten too in the process.

2. ## Re: Average price

Originally Posted by Exige
Hi I am having a hard time figuring out how to finish off this problem any help would be great thanks.

Otis taylor plots the price per share of a stock that he owns as a function of time and finds that it can be approximated by the function.

S(t) =t(25-5t)+18

Where t is the time (in years) since the stock was purchased. Find the average price of the stock over the first five years.

I have started the problem according to my book and I am stuck here is where I have gotten too in the process.

$S_{avg} = \frac{1}{5} \int_0^5 25t - 5t^2 + 18 \, dt$

evaluate the definite integral using the fundamental theorem of calculus, then take 1/5 of the result ...

3. ## Re: Average price

Sorry I am really struggling with finishing up this problem ha ha If I do what I think you are saying I am getting 2500 average price is that correct?

4. ## Re: Average price

Originally Posted by Exige
Sorry I am really struggling with finishing up this problem ha ha If I do what I think you are saying I am getting 2500 average price is that correct?
sorry, but 2500 is not the average price per share ... how did you determine that value?

5. ## Re: Average price

I thought by evaluating the integral SIGH

6. ## Re: Average price

Show what you did to get that value ... I can't fix it unless I see your work.

7. ## Re: Average price

In your attachment you appear to have dropped the first "t" from t(25- t)+ 18.

8. ## Re: Average price

Originally Posted by HallsofIvy
In your attachment you appear to have dropped the first "t" from t(25- t)+ 18.
that "error" still would not result in an average value of 2500 ...