How many strands of hair extensions to one ponytail?

I'm planning to cosplay Anya Earlstream soon~ But I can't figure out how many strands to put in her ponytails.. they're THICK....





http://loli.animeblogger.net/wp-content/uploads/2008/04/3535353.PNG





that's a picture. ^^ Help please!How many strands of hair extensions to one ponytail?
if you need extensions


http://horrorkidz.com/


Ive ordered from them several times, and no one can compare to them.


they are just amazing!





ive tried etsy, hairhxc and hottopic. lol and i personally think horrorkidz is the best quality you can get.How many strands of hair extensions to one ponytail?
The picture doesn't work.