How to calculate number of dry yeast package

[golden_guy]

Hello,
When I use yeast calculator to find how many dry yeast package for a beer, I have to fill 'Cell Density' for the yeast. And I am confusing because the yeast safale US-05 have 6 billions cells/ gram and also the yeast safbrew BE-256 have same number of cells/gram (as it written in manufactured website). Although the yeast safbrew BE-256 can ferment up to 11% ABV but safale US-05 can not. So, how to get the differences between any yeast to get a correct amount of package?

 

[sky4meplease]

Determine how many billion cells you need and divide by 6 will tell you how many grams you need.
Follow the instructions for rehydrating before use.
Take into account your finish ABV when choosing a pitch rate. Higher ABV=higher pitch rate. Knowing your finish ABV will help you choose a yeast strain that will tolerate the finish ABV.

 

[golden_guy]

Determine how many billion cells you need and divide by 6 will tell you how many grams you need.
Follow the instructions for rehydrating before use.
Take into account your finish ABV when choosing a pitch rate. Higher ABV=higher pitch rate. Knowing your finish ABV will help you choose a yeast strain that will tolerate the finish ABV.

Thank you for you reply but you did not answer my question. My question is the two yeast I mentioned it above have same cells / gram but one of them can ferment on a high gravity level and the another one not! What I miss here? Need explain!