Have a tough one. The logistic growth function P(x)=90/1+271e^-0.1222x models the percentage , P(x) of Americans who are x years old and have coronary heart disease. I am to use this model to find the percentage of 61 year olds who have some coronary artery disease.

I am probably not going to be able to do this one by myself and figure it out.

Any one wise on these sorts of models?
Please?

Question

Have a tough one. The logistic growth function P(x)=90/1+271e^-0.1222x models the percentage , P(x) of Americans who are x years old and have coronary heart disease. I am to use this model to find the percentage of 61 year olds who have some coronary artery disease. 

I am probably not going to be able to do this one by myself and figure it out.

Any one wise on these sorts of models?
Please?

anonymous · Answer

replace $x$ by $61$ and use a calculator

anonymous · Answer

$$\large P(61)=\frac{90}{1+271e^{-.1222\times 61}}$$

anonymous · Answer

If I am to round to one decimal place am I going to expect my answer to be around 77.7% then?

anonymous · Answer

http://www.wolframalpha.com/input/?i=90%2F%281%2B271e^%28-.1222*61%29%29

anonymous · Answer

if you are going to round, i would say $77.8\%$

anonymous · Answer

:-( I don't know what I did wrong I got 77.6641188677 for my answer.
Here it is obviously 77.8

anonymous · Answer

it is hard to put this in a calculator correctly
i would use wolfram, that way you can see if you put it in correctly or not

anonymous · Answer

Thanks for the help and the advice. It has been most appreciated. Honestly. :-)

anonymous · Answer

yw