Im trying to work out liquor cost percentages and i REALLY suck at math LOL

Basically, if something costs us $1 a shot, and we're selling it for $10 a shot, i know that is 10% cost, but how do i format this in Excel so that a cell gets the correct percentage displayed?

For example i currently have this....

A1= 0.2125
A2= $3.75

I want cell A3 to have the percentage pour cost, in terms of, a shot costs us $0.2125 but we sell it for $3.75, giving us a X% pour cost.

Whats the right formula to use in Excel to display that in cell A3 as an actual percentage?

The goal is to get below 14% pour cost but i need to know what our current pour costs are based on our existing pricinng structure from the old club.

Regards,

Lee