I say a lot depends on the water content. So your easy question just went to all hell. LOL. Also depends on length of surface. Small driveway and 2-3" seems like someone trying to show off their toys. LOL.
Sorry, Kuch. My bad. I usually do 10-1 but the crowd seems to want Kuch this time...that low is close enough that its not defintely going to be far over 10-1 without some rates.
Here is 10-1.