A silver dollar weighs: 26.73 grams ...

Assume Spot $6
1 oz = 31 Grams
So divide Spot (ol' Spot was a good dog) by 31 to get value per gram (it equals $.1935)

Multiply $.1935 X 90% Silver Content X 26.73 =$4.65 (NOT $5.40 because nornally a Silver Dollar is lighter than one ounce).......

Get it.... Ahhhhggggggg