# Thread: How can get proportions in cricle

1. ## How can get proportions in cricle

Hi all how can i get a proportion in circles & ellipse.
Eg: i have a circle diameter is X, outside the another circle radius is x2, another elipse have maximum perimeter is x4 & minimum perimeter is x5.
How can get the proportion of the circle & ellipse, when i say to anybody something like this circle & radius is equal to 1:2...... how can i do this reference JPG is given below

2. ## Re: How can get proportions in cricle

Originally Posted by manojb05
Hi all how can i get a proportion in circles & ellipse.
Eg: i have a circle diameter is X, outside the another circle radius is x2, another elipse have maximum perimeter is x4 & minimum perimeter is x5.
How can get the proportion of the circle & ellipse, when i say to anybody something like this circle & radius is equal to 1:2...... how can i do this reference JPG is given below

Maybe it is just me but I don't understand your question. By x2 do you mean 2 times X
Where is the x4 and x5 on the elipse. I am really confused.
When you talk of proportions, are you refering to area or circumference or what?
Like I said, maybe it is just me.
Melody.

3. ## Re: How can get proportions in cricle

No Melody, it's not just you.

4. ## Re: How can get proportions in cricle

Forgot X2, X4 & X5
Please check my image, i am created this shape (ITS STANDARD), my center circle (White area) diameter size is X (because this shape some time smaller & larger to media to media ie. i am not mentioned diameter) another circle yellow color, that circle larger than the my white circle, ellipse also larger than the my white circle JPG is attached previous post. My problem is i don't want to given any dimension to this particular shape. If anybody increase the white circle my another circle yellow & ellipse simultaneously increase. i am try to given a some proportion to my audience. how can i given proportion.

5. ## Re: How can get proportions in cricle

Originally Posted by manojb05
Forgot X2, X4 & X5
Please check my image, i am created this shape (ITS STANDARD), my center circle (White area) diameter size is X (because this shape some time smaller & larger to media to media ie. i am not mentioned diameter) another circle yellow color, that circle larger than the my white circle, ellipse also larger than the my white circle JPG is attached previous post. My problem is i don't want to given any dimension to this particular shape. If anybody increase the white circle my another circle yellow & ellipse simultaneously increase. i am try to given a some proportion to my audience. how can i given proportion.
I think that you really muddied the waters with that reply.

In all three cases the equation of the boundary is:
$\frac{x^2}{a_k^2}+\frac{y^2}{b_k^2}=1$, where $k$ is the number of the area.

For the white area $k=1$ and $a_1=b_1>0$.

For the yellow ring subtract white area where
$k=2$ and $a_2=b_2>b_1>0$.

For the purple area subtract whole other area where
$k=3$ and $a_3>b_3>a_2>0$.

I leave it to you the find the areas.

6. ## Re: How can get proportions in cricle

You can assume that the radius of the smallest circle is 1 and express all other lengths in terms of it. For example, the ratio of the sizes of purple ellipse : yellow circle : white circle can be (1.5 x 1.2) : 1.1 : 1.

7. ## Re: How can get proportions in cricle

thanks plato, my maths is not good i try my level best. thanks again.

8. ## Re: How can get proportions in cricle

thanks emkarov.
i am try something like this,. My white circle diameter is 30 and yellow circle draw similar to diameter to picture eg. 32. Then 32/30 is equal to 1.07 its my proportion to all cases 30, 35 40 any numbers its standard. same way is apply for Elise. is it right way