Bridge is a percentage game. You don’t have to remember the exact numbers, but you should have a rough idea. of them. For example, when you are declarer in four spades with eight trumps between  your hand and dummy you  should be aware that missing five cards in a suit the chances are about  67% or 2/3 of  the time, will split 3 – 2, that they will split 4 -1 almost 30% or  less than 1/3 of the time and about 4% of the time they will split 5 – 0.  or 1 time in 25 times. When  you plan your play of the hand you have to know how likely you are to make   and what the chances  are you may go down if suits do not break favorably.

 While in matchpoints you generally go with the odds, you should be aware that the  The odds may not be favorable in every suit.  In IMPs or rubber bridge overtricks are not nearly as important as  they  are in matchpoints or board a match . You have to  be aware the that it is very possible some suit will  break  in a way that is least favorable and  should look for a line of play that will  to ensure making your contract even  though one or more suits may break worse than is to be  expected to be the  acording to be the  the most likely  percentages .