e/Rule of 10-12

Information
has gloss	eng: In bridge, the rule of 10-12 is applied when the opening lead is the third or the fifth best from the defender's suit. By subtracting the rank of the card led from 10 or 12, a defender can figure out how many cards are higher than the card partner has led. 10 is used if the lead is fifth best and 12 is used if lead is the third best . Rule of 11 applies when lead is the 4th best.
lexicalization	eng: rule of 10-12
instance of	c/Bridge leads